Thanks again for all the thoughtful replies.
New recommendation from friend, want to know if this is plausible/possible:
Buy a spec'd out HT, top of the line (for example, a nice Stumpy). The following year, also buy the all-mountain frame from the same line (i.e. the Stumpy FSR frame).
Are those sorts of things totally transferrable to the FSR frame? Or is the angle of the fork going to be an issue? Can I just buy a frame and a 2nd BB and rebuild the Stumpy HT as a Stumpy FSR if I were to move to a place where such a bike would be useful? 'Cause right now every trail in my area you can do on a 'cross bike, if you're a competent rider, that's how "prairie" I'm talking.
What else would need to be purchased to throw all the parts over to the FSR frame?