I got my 1.83 gHz Rev C MBA a few days after they were out, but I haven't had time to do much with it - until today. So, here's the nuts and bolts for high def video play. Straight Blu-ray rip playback. Source is a straight rip of Iron Man Blu-ray disc (1080p), which is very high bit rate (around 40 mbps) with AnyDVD HD and contains the True-HD audio track. I used Plex for playback, which transcodes the True-HD audio to Dolby Digital 5.1 on the fly, which then gets downsampled to Dolby Pro Logic for the MacBook Air ( up to 5 channel surround). Result: Lots of dropped frames and really not watchable. Blu-ray rip remuxed with tsmuxer to Dolby Digital 5.1. TSmuxer extracts Dolby Digital AC3 core from True-HD and DTS from DTS-HD audio and repackages it into an m2ts (or ts) container, preserving the original Blu-ray disc video source (h.264, MPEG-2 or VC-1). This makes it so Plex does not have to transcode the audio on the fly, thus alleviating pressure from the cpu. Same movie (i.e., no change in video quality from the disc), but dramatically different result. Result: Silky smooth playback of the 1080p source down to 720p on the MBA display. There were only 8 dropped frames right at the beginning (typical of Plex) but no more after that. Piped this to my 1080p Sanyo projector from the Mini DisplayPort and it worked just fine. In addition, I used Quicktime to play Ratatouille that had been transcoded from Blu-ray to m4v with Handbrake (1080p, 14 mbps, H.264 with Dolby Digital 5.1) and Quicktime played it perfectly fine (other than not being able to deal with the Dolby Digital track). So, it looks to me that the new MBAs are pretty good at playback of high-def video. It's definitely better than the 1.83 gHz Mac Mini/GMA950's ability to play Blu-ray video. Let's hope that at some point Apple will enable digital audio over the Mini DisplayPort so that we can passthrough high-def audio as well. This would also allow playback of the original source (i.e., the problem I have in #1) because Plex could be built to passthrough any high-def audio. In other words, I think the Rev C MacBook Airs are Blu-ray ready right now.