All I'm going to say on the matter is that unless there is a very urgent need to divide or merge cultures (except Southslavic, which I'm not going to touch anyway

), *and* it can be done without messing with the name lists (which the bugfix doesn't include), it's probably not worth bothering with, esp. since culture doesn't affect a whole lot.
It might change if folks clamor for me to include the names file in the bugfix, though I warn you that you'll be saddled with my version of it in that case, and will have to do any personal changes on your own.
Alternately we could include a "name list addendum" with only names for new cultures (norse, ugricbaltic), which would require mod users to manually add it to their names files. If people think this is a good idea then we can do it that way too. It's the option I personally like the most, if we start messing with name lists.