Here, here.
Yes, it's interesting and I'll probably buy one. (After things settle a little.) But, what about the Beagle Bone? It's a bit pricey in comparison, and I don't know whether it does 1080p decoding, but otherwise, it's an Arduino running on a 700MHz ARM processor. GPIO is already available on the BB. It's an option for the RP.
So, if the AVRs were going to be threatened by a core clock speed makeover, that ship would have sailed by now. Fact is, there's plenty you can do at 16MHz. There's no need for near-GHz speed for many of these projects. There's plenty of room for low-power processors. Right tool for the job and all that.
I would also like to strongly second the discontent with proprietary chipsets, though I don't know that there's any option out there for hardware-accelerated 3D and video decoding that isn't going to be swamped in patents and NDAs. That's what we, as a society, get for allowing the fancy HDMI, Dolby, and MPEG logos to sway us away from perfectly good open and patent-free alternatives. Now, if you want to play commercial content, you have to be licensed to decode those formats. That costs money. To ensure those fees get paid, the libraries aren't available for free. (Part of the Pi's cost is licensing of MPEG4/h.264 codecs. No MPEG2 yet.) And since there's no point in restricting release of binaries if the source is available, you don't get that either. Which means you're stuck with the drivers and kernels made available to you. Happy tinkering! Far cry from the BBC micro in that sense.
Sorry. Touchy subject for me. 