Nope, won't be buying one this year for a few reasons:
1) Being a Microsoft fanboy means I use Excel to manage my finances, as far as I know, a Surface Pro isn't in the books for this year when I have several other priorities, one being a pricy desktop rebuild for the Windows 8; which a Surface Pro is about half the cost of it.
2) I don't have a need this year for a secondary PC. When I go back to school, I will, but for right now again, I want to rebuild my desktop for Windows 8 and get a 27 inch IPS touch monitor when one finally comes out, as well as having SO much computational power that I literally won't know what to do with it. Maybe play Grand Theft Automobile 5?...
3) It's rumored that the Surface Pro 2 later this year will feature an AMD APU processor over an i5. This means it will pack a REAL potent graphical punch, which is what is needed for Photoshop, AutoCAD, metro app rendering, and pretty much every other bit of digital media software. I'm an AMD fan, so I'll take that over Intel. Also, it should come in an 11.6 inch touch screen as well...so...yeah.
But to speculate on the low shipments of the Pro, I have to say it's a combination of low supplies and more than expected demand with a bit of artificial scarcity involved. The RT when launched, sold out in a couple of days I think it was. The Pro did the same, with the 128 gig model sold out the first day. And seeing since the Pro came after the RT, I have to wonder if there were part supply issues with it, as the Surface tablets have like....200 custom designed parts? It's a VERY new product, with a healthy amount of demand, but not enough stock.
The same thing is happening with the Nokia Lumia 920, for some people it took weeks before they got theirs after launch. The red one was recently replenished, the yellow one as well as that seems to be a HUGE seller; at least in China with the 920T. The latest Lumia Windows Phones have been met with a healthy amount of demand, but stock isn't enough to supply that demand.
In hindsight though, it's better to have a low supply issue and high demand versus high supply and low demand...