It was supposed to automatically uninstall SDLMAME as part of the installation, but HAM doesn't fully follow the debian package hints, so you should do it manually.

Regarding the change of name: the MAME people aren't any more involved with Maemo than they were before. What has changed is that SDLMAME, which was formerly a side project to allow MAME to run on linux and MacOS and such, is now an integral part of MAME. It's a good thing because it means that a tested and functional SDL port is (in theory) part of each MAME release now.

I don't anticipate huge differences between this version and the previous Maemo release. There were some fixes to autosave which might be relevant. I'm just relieved to have a working port again after the merge.

I'm going to upload another version tonight that will have the usual hack to fix the non-QWERTY keyboard issue and also automatically start and stop accelemymote if it is installed. I'm looking at ways of improving the menu but it's implemented in the most general way possible, meaning that what might have been hacked together in a few pages of code comprises a few hundred kb of code.