If you can get the parts and PCB, you have the logical methodical mind of a programmer, and you can learn to solder, you should be able to build it. SMT soldering is one of the harder sorts, but if you learned how to solder correctly you can do it.
Once you can solder, I'd put it at 'challenging but enjoyable, spend 2-7 late nights'
I don't think itd take anything like that long. It looks like there's 15 (smd) components, 11 jumper wires, a 6 pin header and 4 wires from the joystick - anybody who's ever successfully soldered smd components before could easily put this together in under half an hour.
Have a look around and see if you can find a local hackerspace, there's probably half a dozen people at my local one (free plug for http://robotsanddinosaurs.org ) who'd do this for you any Saturday afternoon...
I still reckon the parent poster should seek out a hackerspace or similar, so he can spend those nights 1 through 6 debugging his game instead of the hardware...
Actually, you don't need no stinking SMT. The parts are way big enough to solder via the more traditional methods. And even better, you don't need SMT-style casings for the resistors, etc. their wired counterparts are readily available (albeit not as pretty).
Speaking of developing games for it, how does that work? I see the word 'flash' mentioned a few times, is the author talking about the same technology people make games on the Internet with?
No. You're thinking of Adobe/Macromedia flash. The word you're seeing relates to a type of memory (and more recently) a process of storing data in that memory.
You're going to need to know either C or the architecture assembly (and probably both to do much beyond "hello world"). If you're not a programmer (inferring from your comment), there are some arduino game kits which are much more friendly.
C and assembly should work pretty well. As an alternative you can also look into Forth, a cool language that's easy to get running on the bare metal, and spans the levels from assembly to C and above.
A Forth machine is almost as amazing as a Lisp machine, and the language share some similarity in spirit, also (or maybe because) they are almost their exact opposites in almost all technical aspects.
[1] http://ics.nxp.com/lpcxpresso/ [2] http://search.digikey.com/scripts/DkSearch/dksus.dll?lang=en...