I've been fortunate enough to go to Vegas a fair amount over the years, I've stayed at more than half a dozen different places (cheap & expensive) on the strip, and the Venetian is easily my favorite-both from before & after I turned 21. This includes more expensive spots like Wynn. Good location, beautiful surroundings and atmosphere (probably comes as close to NOT being just skin deep luxury as I've experienced in a city where smoke & mirrors is everything), and obviously a great club.
Top to bottom, it's just really high quality and the real deal.
Haven't stayed at Bellagio or the newest places (like Cosmo-seems amazing when I've hung out there) but I do know that if you have the money to stay anywhere, you'll be happy staying here.