[drdaeman]

I believe it's more about tight vs loose coupling, not integration. The contrast is, systemd's parts are relatively tightly coupled together (in a way one can't easily pull, say, journald and use it autonomously, with other init), while, traditional init systems are bunch of loosely coupled mostly autonomous modules that happen to reliably work together thanks to standards' glue (so, they're integrated as well).

I could be wrong on this, though. Just my thoughts.

[keithpeter]

I suspect the 'standards glue' is an important aspect of all this. With loosely coupled modules and standardised glue you can update components separately on different time scales and be reasonably confident that they will still integrate with other components.

Tighter coupling with rapid integration in functions and therefore changes in glue makes it harder to work piecemeal. Distributions have very different time lines. Pity the packager stuck trying to back port patches to an earlier version of the system when the upstream project(s) is(are) pushing out security updates based on the current versions and their current glue/api.

Of course it will work and work well. Redhat are betting their major product on this set of modules. The problem will be the load on other projects working around this.