Some are saying this kind of device is useless and it is just as cost-effective to build a PC. This reasoning is fairly sound, but it neglects a few important factors. First, some of us do not want a large PC (and even Micro ATX is large compared to a laptop) weighting us down. I don't spend a lot of time in front of a computer at home. While I am there, I like to have things neat and clean and quiet; this is impossible with a large PC desktop. I've dealt with those for years and gaming on them is great. However, they too become dated and require updating.
Second, it's not necessarily cheaper to build a new PC than to buy this external GPU case. Version 4 is roughly $250-$300. A respectable graphics card might be another $200. That puts us at about $500 (unless, like myself, you have a spare GPU lying around, making this a much better deal). A decent PC will cost about $900 and that's not including a monitor if you need it. So, you're not having to lay as much down for this unit when you already have the MBP (Air, etc) to plug into it.
There are definitely downsides to this product, not least of all the lack of Mac drivers for all the various cards out there (though Boot Camp may be a respectable alternative). Then there's the Thunderbolt support to consider. If I could plug this product in and my Mac recognised it instantly, then we'd be on to something. However, it doesn't seem like it would be one of those products that Apple would include native drivers for in its next OS install (disc, download, USB stick). However, the promise is great and anything is better than the Intel HD 3000 in this 13" MBP.
I just wonder what happens when you plug it into your computer. It only supports an external monitor. Does that mean your MBP (Air, iMac, etc) monitor just goes black while this is plugged in? Can you just close your Mac while it's being used in this way? Anyway...I'm still excited about this news and after a few reviews start rolling out if this thing is ever developed, I'll jump on the chance to purchase this. I will then be able to avoid the purchase of an XBOX 360, which I was considering to replace the PC I just dismantled and took to the dump. Do I really need any more excuses to waste my time? Perhaps. What a shame people keep coming up with cool s***. I gotta stop spending money, as I have an engagement ring to budget for! =P