I have such trouble bringing myself to spending miles, in part because redemption is so damn difficult (especially on DL where I have the most miles right now) ... but I have spent a good bit on US the past year (eight awards total for a little over 500k), in part because I 'bought' 500k worth in late 2009 with their silly Holiday promotion.

Right now I have what I call 'useful' balances (at least 25k miles) in AA (250k), BA (250k), CO (35k), DL (500k), F9 (40k), UA (50k), and US (400k) plus awards on WN, so in total I'm at 1.5 million between my various accounts, add in my wife's accounts and we're probably a hair over 2 million. I consider myself 'poorer' in hotel points, though I've got enough to spend several weeks in luxury hotels if I wanted just between Hilton (450k) and Hyatt (230k), with lesser, but still useful, amounts in Marriott and Priority Club. I also have an AMEX Membership Rewards account and Diners Club Rewards account with 30k+ each (I redeemed 50k out of AMEX last month for the DL MQM promotion) giving me some liquid points that can go in several different places if and when needed.