Presumably, there are some smaller bug fixes in the update, but we'll have to do some testing to confirm that. The only item listed in the change log for the update is a fix to restore ringtones that you might have purchased from iTunes, and had been removed unexpectedly. That sounds like a fairly low-impact issue that probably didn't have too many people who were affected (and even fewer who would have noticed that anything was missing). But, it's always nice to have a fix for a problem.
It's a small update,and it is available over-the-air right now. But, we do know that there is a major update on the horizon. Apple has already seeded iOS 8.2 to developers, which brings support for WatchKit. The Apple Watch is expected for release in the spring of 2015, so it is likely that iOS 8.2 will be hitting around that same time.