Brad,
It really depends upon the kind of stuff you're interested in. My parents have a vacation condo about 15 mins. from the strip, and I get out there about once a year. There are plenty of shows to see...check vegas.com to see what's available. There are alot of good free things to see also...fountains at Belagio, pirate show outside Treasure Island, Lions at MGM, animatronic shows inside Caeser's Formums, and don't forget the Fremont St. experience. Blue Man Group is a decent show. There's an IMAX at the Luxor. If you've never seen a Cirque du Soile (sp?) show, there are four of them at various hotels (My favorite was "O" at the Belagio), and I highly recommend them...it's much more than a circus (go with the GF...she'll love it). If you like thrill rides, try the "Big Shot" on the top of the Stratosphere...WEEEE! The Hoover Dam tour is interesting, as is the Valley of Fire. Obviously, gambling is available 24/7... so pace yourself. If you've got a couple days, you're only about a 4-5 hr. drive away from the south rim of the Grand Canyon. Oh, and if you're interested in a bit of the more risque side of town, just hop in a taxi and tell them what you're looking for.
Don