I've read about the difference between Service Packs and Cumulative Updates but I'm not seeing any official guidance on whether to install CUs as they come, or wait until they're rolled into a SP. Generally a CU is a collection of Hotfixes and the advice for those usually says not to install unless you are suffering from the problem the Hotfix solves.
It looks like this is an 'it depends' question. So:
We wait for the SP.
Why?
As you suggested above, we would only apply the CU if it contained a hotfix that we needed.
+1 @ CirqueDeSQLeil, but got some bits which won't fit in a comment!
I think it's worth posting up the link for the Connect item for 2008 SP2.
Another thing to point out is that service packs go through a more rigorous testing cycle than cumulative updates do. However, from reading this blog post one might come away with the opinion that cumulative updates are thoroughly tested and that service packs are now more frequent. From where I'm sat, I can't really see any evidence to corroborate that - yet. Microsoft is a huge company though, so I guess it takes them a long time to change. We'll see.
