the pi is about $20 cheaper than my first arduino and about 35x faster (forgetting the fact that its 8-bit vs 32-bit), not to mention it has an fpu and gpu while an arduino does not. even if it doesnt pan out in the running freespace department im sure i can use it for my other freespace related ideas. not to mention many a hardware project thanks to its gpio capabilities.
I just checked the prices, the R-PI B is about 50-55 usd with shipping with unknow avalibility.
I quick search on ebay i get (im not going to post links): With the AllWinner A10 processor
-100usd for Mele A1000 TVBox (512MB ram, with all video outputs, ethernet and a real SATA port)
-90usd for Mini X (1gb ram, remote control)
-75usd for MK802 (1gb ram)
All free shipping, every one of them comes with a case, DC adapter, some even HDMI cable, Wifi N, 4GB internal flash, dual boot Android 4.0.3 and Linux(and soon XBMC), very high bitrate multi-format 2160P VPU(with 3D support somehow), and a 1 to 1.5ghz ARMv7 cpu, so yeah, R-PI is cheaper and have a better gpu (Mali-400 on A10), but if i going to have something to use as a HTPC with capability to play FSO its not going to be the R-PI, also there is a lot of cheap A10 tablets out there.
It depends on what use every one of us want to give them.