Just dropping in to mention that context menus are not working for me (they're not visible) in Windows 8.1. It worked fine in 8.0.
I use 7zip 9.20 x64 stable, but I tried 9.22 beta (32 bit), 9.25 alpha (x64) and 9.30 alpha (x64). It seems to work in 9.25 and 9.30.
On a side note, I noticed the default install location in 9.30 was going to "Program Files(x86)" instead of "Program Files".
Anyway I just wanted to Share about Windows 8.1 since it's new and stuff. Having said that, do you think using 9.20 "stable" on 8.1 is really any safer than using an alpha? (In other words, I'm guessing neither is recommended yet.) I do much more extracting than compressing (like 99 percent of using 7zip) so I'm not too worried about data loss.