I've moved most of my development work over to the in-development 7.7 builds (and thus, many of the screencasts as well). The builds have been getting more stable, and there are a lot of nice things in there - browser improvements, as well as a nicer experience on the Mac. Support for the Mac menu won't be in the release, but as I said a few days ago in a screencast, it should be possible to add it to your applications using the new Objective-C connect.
There's also been one annoying bug on the Mac that's gone: the "sticky" menu problem, where a menu would stay up after you made a selection. As it happens, in 7.6 that was actually a second menu. That's gone, and it makes a huge difference. The entire environment seems more responsive as well - I think you'll like it. We're targeting August for the release, so stay tuned, and watch "Smalltalk Daily" for more details.