I seem to recall from Brays blog that he too shared Cantrills lack of enthusiasm for working for Sun, but was drawn in by the culture. It seems that Sun was an outlier in the huge-company-enterprise space in having a great hacker culture, and that brought in some people that would otherwise be more at ease in smaller companies.
Oracle can't/won't/isn't interested in keeping that culture around, and it is questionable what that culture actually brought about in value at Sun. After all, they weren't very good at making money. Oracle, on the other hand, is very good at making money, and perfectly happy letting the cool people work other places, acquiring their work if they decide they need it.
It might not even be that Oracle isn't interested in that culture so much as Oracle simply isn't Sun and that was Sun's culture. Sun believed Sun was the best and everything else wasn't. Sun believed in Sun, quite a bit, enough so that Sun wouldn't wake up and smell the coffee when the CEO was blogging about a filesystem in the 21st century.. (You know, I couldn't tell you what filesystem gmail is on or amazon uses or salesforce.com uses, since we dumped FAT nearly 20 years ago, I haven't really had much reason to care other than because I'm geek. It's not impacted performance in anyway that would hurt business, just as one example.)
If there was some sort of news from Oracle, how they weren't interested in a class of products or they weren't interested in technology or anything like that, or maybe all all the senior sun guys were being demoted a notch or seomthing then folks would be screaming bloody murder and we'd all know about it. Oracle wants to continue to make money and Sun was more interested in making their team think they were the best, regardless of what the market showed. That's the difference.
Some of these guys simply might be better off elsewhere, their time might be past, but if they really want to show their greatness then they have an opportunity to do so now with real marketing might. I went through this with a company a few years back, we boot strapped it, got it going, came up with some good ideas and some products but didn't have the money to make them robust and didn't know how to sell; we got bought and maybe a quarter of the team saw that as the ending (nobody made any money at that point) and they put that kind of effort in, the others saw it as time to get real and do the hard work, take things to the next level.. It's just a natural sort of thing when companies get bought.
On the up side, I give the guys that are leaving some credit. They could just hang out and be dead weight, draw probably giant pay checks and not do a whole lot.
Based on Gosling's blog, "enrage" might be a correct characterization ("an awful lot [ of my time ] has been taken up talking to people about life at Oracle. They need a place to vent, and I try to be a good listener.", that's from about a month ago and the whole short item is worth reading: http://nighthacks.com/roller/jag/entry/escaped_from_reality)
One very simple thing we do know about is that many/most?/nearly all??? of Sun's software people have seen their salaries significantly reduced. Even if this didn't hit directly people at Gosling's level it would substantially change a whole lot of things and certainly sends a number of negative messages.
It's not completely grim, the Maxine (JVM in Java) research group seems to be very productive and not losing principles, but they're working on an area that Oracle considers to be critical (JVMs in general and JVMs on top of VMs in particular).
Oracle can't/won't/isn't interested in keeping that culture around, and it is questionable what that culture actually brought about in value at Sun. After all, they weren't very good at making money. Oracle, on the other hand, is very good at making money, and perfectly happy letting the cool people work other places, acquiring their work if they decide they need it.