I'm not sure what you're talking about here... GnuCash has built-in multiple currency support.
In my opinion, an important issue with GnuCash is that development is fairly slow due to a good chunk of the codebase being LISP, which limits the universe of developers that can work on it. Unless they've changed that with this new version (which would be great!). So it seems like the pace of development compared to other open source products of its age is fairly slow.
I'd like to see the reporting and graphing features fleshed out a bit more, these seem somewhat limited. All in all, though, it's a pretty nice program.