Just an update.

Glad I didn't wait on the Raspberry Pi, I don't imagine I'll get my hands on one until sometime Q1 2012 at the earliest. I still plan to order when they do become available with the order date pushed back to Decemeber (and I expect more delays much like OpenPandora project)

Purchased a WDTV Live Plus (v1; v2 is now out) about a month ago on sale, very happy with it. The stock firmware (1.05; 1.06+ is buggy) is very good. Recently I got around to flashing the latest WDLXTV community fw and it is amazing. I was able to program the box (rather than my "universal" remote) to accept the IR codes as well as able to trigger them via a web interface. Now have ssh access, "app" addons, usb boot and more.

Not a general purpose computer like the RasberryPi but it does play EVERY video I throw at it. Good HTPC, SAMBA media streamer and online streamer (youtube, vimeo, flingo, shoutcast, etc.) and I'd recommend it. Don't pay more than ~$60, shop the sales, use coupons, etc.

Just my 2 cents.