Last night, with the 2.3 software update (and a freshly-activated Boxee account) calling to me, I decided to try updating my Apple TV once more through the use of a patchstick. Downloaded the excellent atvusb-creator, and Apple's own 179MB 2.3 update DMG (direct link); put two and two together and got eight, as atvusb-creator added SSH+FTP access, plus a launcher for the Boxee and XBMC media interfaces. All went really well, and all I had to do once the Apple TV restarted under the new firmware was install the add-ons using the customised interface.
Boxee is a joy to use; I only wish I could say the same about some of the content providers it offers inroads to. Hulu is a total waste of screen space, as all its content is US-only. MTV's channel is even more annoying, as some of the music videos are US-only while others aren't - it's only when you find something and try to play it that you get the obnoxious "no pony" message up on screen. Anything you can't watch is still logged in your Boxee feed as having been watched, which is also irritating.
BBC iPlayer's interface, on the other hand, is brilliant, mainly because nothing's off-limits and I no longer have to illictly download off iPlayer only to re-upload to the Apple TV. I was watching full episodes of The Daily Show and South Park through Comedy Central's channel, although again I encountered sporadic problems streaming video, with one South Park ep coming through in black and white which was odd. CNN's channel is useful for the odd news clip, and one day I'll get around to adding my own video feeds from other sources.
The XBMC media interface looks definitely more polished, but there are a few bugs still to be worked out: mainly the one where if you return to the menu while watching a video, you can't access the small playback controls using the Apple remote to go back to full-screen mode. I have to admit though, watching the main menu blended into a currently-playing episode of Fringe looks quite nifty. Both interfaces have the overscan problem licked, with a nifty interface to control visible corners and aspect ratio.
I'll go back to playing with my infinitely-more useful Apple TV now; if anyone wants a Boxee account, let me know.