LedgerSMB is on Sourceforge and probably will never move. Moving is a lot of work. Sourceforge has some quirks but it isn't really all that bad. Even for projects on GitHub, it's not bad to have a Sourceforge presence for hosting downloads and the like. It is true that in general we have been trying to move more and more of our services off Sourceforge, but this has been a slow process.
Sourceforge offers a lot of things that GitHub and Bitbucket don't offer. I haven't been able to find email list hosting integrated with project management anywhere else yet but maybe I haven't been looking hard enough. The closest thing you have is Google Code.
I wouldn't say there's anything wrong with it. It isn't as trendy as some others, but I think you want to look for concrete benefits, not worry about where the hottest spot is at the moment.