As far as handling characteristics, I would look mostly at head angle, chainstay length and bottom bracket drop vs. BB height. HA is very important to me because I tend to like bikes a bit slack; CS length, especially with 29ers, govern how 'snappy' they feel on the trail; and BB drop is what imparts the "in-it-not-on-it" feel - - again more pronounced in 29ers - - but weighing that against BB clearance. Don't want it too low or you start having pedal-strike issues.
Beyond that, I really wish all MTB companies would drop the antiquated TT/ETT and seat tube length and give us the Reach & Stack numbers.
__________________
Originally Posted by Mark Twain
"Don't argue with stupid people; they will drag you down to their level and then beat you with experience."