Don't want to wait on Windows Mobile 6.5 but don't want to mess with hacked ROMs, either? XDA Developers (who else!) has got you covered.
If you have a QVGA phone and SPB Mobile Shell Verson 2.1.5, you can download a theme that will skin your phone like WinMo 6.5. Pretty slick. But, yeah, the problem is it's only available for QVGA phones right now. Let's hope that gets scaled up real soon.
But if you're in the market, head on over to XDA Developers and try out mtstmp's creation.