A big screen t.v. for 27265 AP miles? Forgetaboutit.
Tough call on the points.com thing, but I'd say hang on to the AC AP points and wait until Futureshop has some promo like 10,000 miles for big screens and pay for it on a cc that gives AP miles. So why not triple dip: get Diners Club enrollment 12,000 bonus, pay for big screen at Futureshop with that card and get miles for charging the purchase to the DC card AND get any bonuses Futureshop may be offering. Could work out to around 25,000 more AP miles.