Hard call: I'd have to say it all depends on the author's intent.
Let's see ... at the time he wrote "Neuromancer" William Gibson had never used a computer -- he wrote it on a manual typewriter (and used the royalties to buy an Apple IIc). His creative vision was more one of social atomization and a particular aesthetic in a multi-national dominated future than it was informed by actual technology. Despite which, his creative vision of "cyberspace" got taken seriously enough as a visual metaphor that I remember sitting in on a debate at the W3C conference in 1996 between folks proposing that VRML should follow a Gibsonian model, and those who thought "Snow Crash" was the way forward. (Neal Stephenson's followers won the day. See also "Second Life", I guess ...)
That's an example of "influencing". "Neuromancer" was very influential, but hardly predictive.
Actual predictive SF is much, much rarer, but if we ever get a space elevator you can probably blame Arthur C. Clarke ("The Fountains of Paradise"), which is an old-school didactic hey-why-don't-we-do-this-the-numbers-check-out work of prediction in fiction drag. Or maybe Andy Weir's "The Martian".
Written SF has traditionally been utter rubbish at predicting developments in the IT/computing sector, with notable exceptions -- for example the novella "True Names" by Vernor Vinge. (I've attempted this too but I'm not going to bang my own drum here.)
All other metrics aside, Heinlein always impressed me not only for being something of a polymath, but for his prescience in some areas.
In particular, I often find myself citing his depiction in _Friday_ of its titular character using a multimedia hyperlink system which seems analogous to the web and media-rich hypertext generally. (He gets wrong that it's an exclusive closed private system... that is wrong... isn't it...)
It's not the depiction of hypertext research that I find compelling...
...it's his dead-on intuition that such systems will naturally lend themselves to browsing by associate leap, far afield from the original research topic. And that serendipity and unanticipated (and unsought) correlations will prove both more compelling to users and more illuminating that narrow document retrieval would be.
Whether that same book paints a reasonable depiction of the current devolving global political climate is another question... but one which also continues to come up in idle conversations...
Btw @cstross just finally read Saturn's Children, Neptune's Brood, and the connective-tissue short work whose name escapes me. I greatly enjoyed the winks esp. in SC to _Friday_ etc. Thanks!
Heinlein stated writing "Friday" in 1981. This is well after Vannevar Bush's highly influential "As We May Think" from 1945. It's hard to find someone in information retrieval in the 1950 and 1960s who wasn't directly influenced by Bush's Memex. One of those is Ted Nelson, who coined 'hypertext' and wrote "Computer Lib / Dream Machines" in 1974. This book in turn influenced the early microcomputer hackers, which is the era when Heinlein wrote Friday. (Eg, Jerry Pournelle started writing for BYTE in 1980; there isn't a huge gulf between SF and microcomputers.)
You regard Heinlein's 'dead-on intuition that such systems will naturally lend themselves to browsing by associate leap' as being prescient. I can't say what you mean by prescience, but I can point to "As We May Think" to show the importance Bush placed in associative thinking some 35 years earlier:
> The human mind does not work that way. It operates by association. With one item in its grasp, it snaps instantly to the next that is suggested by the association of thoughts, in accordance with some intricate web of trails carried by the cells of the brain. .... Yet the speed of action, the intricacy of trails, the detail of mental pictures, is awe-inspiring beyond all else in nature.
> Man cannot hope fully to duplicate this mental process artificially, but he certainly ought to be able to learn from it. In minor ways he may even improve, for his records have relative permanency. The first idea, however, to be drawn from the analogy concerns selection. Selection by association, rather than indexing, may yet be mechanized. One cannot hope thus to equal the speed and flexibility with which the mind follows an associative trail, but it should be possible to beat the mind decisively in regard to the permanence and clarity of the items resurrected from storage. ...
> Wholly new forms of encyclopedias will appear, ready made with a mesh of associative trails running through them, ready to be dropped into the memex and there amplified.
I can also say that in 1951 Heinlein was well aware that research was much more than 'narrow document retrieval'. Consider "The Puppet Masters" from that year, chapter IV:
> "At the library I went to the catalogue, put on blinkers and started scanning for references. "Flying Saucers" led to "Flying Disks," then to "Project Saucer," then "Lights in the Sky,", "Fireballs," "Cosmic Diffusion Theory of Life Origin," and two dozen blind alleys and screwball branches of literature. I needed a Geiger counter to tell me what was pay dirt, ... Nevertheless, in an hour I had a handful of selector cards. I handed them to the vestal virgin at the desk and waited while she fed them into the hopper."
That's catalogue-assisted associative thinking, followed by document retrieval. I don't think requires prescience in the early 1980s to get a sense for how a Memex-like machine embodied in a modern computer might improve upon a paper catalogue for associative thinking.
To be more concrete, remember too that France was rolling out Minitel across the country the same year Friday was published. While Minitel specifically did not likely influence Heinlein, I bring it up to show that the ideas of online research terminals was no longer pie-in-the-sky dreaming, but something that many people thought about and were implementing. (Another example from two years later is the 'the Bloomberg terminal', which is now a mainstay of business research.)
(Minor disambiguation fix; too late to edit: I wrote "One of those is Ted Nelson", in a context which makes it sound like Nelson was one of the small number of people not influenced by Bush. The opposite is true. Nelson was one of the many influenced by Bush.)
Let's see ... at the time he wrote "Neuromancer" William Gibson had never used a computer -- he wrote it on a manual typewriter (and used the royalties to buy an Apple IIc). His creative vision was more one of social atomization and a particular aesthetic in a multi-national dominated future than it was informed by actual technology. Despite which, his creative vision of "cyberspace" got taken seriously enough as a visual metaphor that I remember sitting in on a debate at the W3C conference in 1996 between folks proposing that VRML should follow a Gibsonian model, and those who thought "Snow Crash" was the way forward. (Neal Stephenson's followers won the day. See also "Second Life", I guess ...)
That's an example of "influencing". "Neuromancer" was very influential, but hardly predictive.
Actual predictive SF is much, much rarer, but if we ever get a space elevator you can probably blame Arthur C. Clarke ("The Fountains of Paradise"), which is an old-school didactic hey-why-don't-we-do-this-the-numbers-check-out work of prediction in fiction drag. Or maybe Andy Weir's "The Martian".
Written SF has traditionally been utter rubbish at predicting developments in the IT/computing sector, with notable exceptions -- for example the novella "True Names" by Vernor Vinge. (I've attempted this too but I'm not going to bang my own drum here.)