He might be "being ark" but that doesn't make him any less right. That's a really good deal, for now, but by this time next year they'll be throwing ouya's in as free bonuses with real purchases.
If you were planning on getting on anyway, I would jump on it, but otherwise you are getting a second controller for a console that mainly features 1 player android games.

Howard: Have you seen any of the games on the OUYA? It doesn't feature 1 player android games at all...it features OUYA games. Its a night and day difference (sure its OS is android but its also more than that.)
That and most of the top games are living room multiplayer games that you play with your friends/kids. Google
bombsquad if you want an example.
Most of my play time on the OUYA is multiplayer with my kids...(so Howard no 1 player android games for me.)
That doesn't mean there aren't good single player games on there or some that are also out on android (Sine Mora) In fact some of the games are coming from XBLA just you don't have to pay for Live.
There is a good amount of crap too...just like in the arcade world. Sure a year from now the hardware will be cheap...but Using it and having fun with it for a year is worth it IMHO.
If you want to spend $100 more and get a surface great...but we are talking about playing games and consuming content on a TV with a controller. There are plenty of good tablets out there. So what.
Ark: I doubt the MK808 has the same games that you would "want" to play. LOL and the controller is proprietary but it is Bluetooth so who knows there might be ways to make it work.
Snake: yes you can use any HD...I just stream from my NAS but either way XBMC is great.
PBJ: Yes, Yes, Yes, no and Yes. I enjoy seeing what it can do. To clarify, you can watch whatever you want...and emulation including MAME works great.
LOL
/soapbox