Using an Arduino as a robot controller (2010 and beyond?)

[Leav]

Hi Everyone,

This post is somewhat intended to help me understand what makes the (very expensive) IFI and NI controllers superior (are they?) to the (very cheap) Arduino and it's family.

I have recently been introduced to the Arduino through the RepRap Project that i'm working on (<-- check it out!) and it seems to me that it has great potential as a cheap robot controller (which in fact is one of the major uses it is put to by hobbyists).

But before I can go out and propose that in 2010, when a 2009 rookie needs a controller for their 2009 robot for demonstrations, they can use an Arduino... I need to know if it will work!
(So for argument's sake let's just say I am proposing this, and you can explain why it won't work )

So if anyone is willing to give me a hand here with a short microcontroller primer, i'll be very grateful!

Thanks!
-Leav

p.s.
Don't you think grateful is spelled in an odd way? "greatful" would have made more sense to me