I have not purchased any next gen handheld. Vita seems cools, but 3DS is still my 1st choice if I get one at all. I am usually at work or at home, I cannot play games at work, and at home i have a kickass PC/PS3/Wii so Handhelds dont really have a niche for me. Oh and when I go on trips I usually drive the entire way...
When I was in Iraq my DSXL got good use, so if I get deployed again I may upgrade to 3DS.
End of 2009 Predictions (Set, January 1st 2009)
Wii- 72 million 3rd Year Peak, better slate of releases
360- 37 million Should trend down slightly after 3rd year peak
PS3- 29 million Sales should pick up next year, 3rd year peak and price cut