I had a great, very memorable time during my first time at Tao but after that each experience hasn't been up to par since then. I typically like to make my way to the smaller rooms and avoid the main area due to crazy overcrowding. I love the decor of the club; it's very enticing. But overall, Tao has become an overhyped disappointment.
The overcrowding is comparable to PURE at Caesar's Palace. It's gotten to the point where it's practically unbearable. Couple the overcrowding with trying to navigate the multi-floor maze that is Tao and you're in for a headache. I do like that they have Tao Beach for those who need some air but trying to find it is a real pain. The music is ok and the crowd... meh. I can't believe they let anybody in, especially if you're wearing an Ed Hardy shirt (but I guess that goes for any guy in Vegas who doesn't have his own style but wants to fit in). So much for the upscale dress code.
Each time I've gone to Tao, I was a hotel guest at the Venetian (otherwise generally be prepared to WAIT a while). I've only had to pay cover once but the other times I've been to Tao, I've had complimentary passes. I can honestly say that I'll be avoiding Tao from now on, regardless of whether or not I stay at the Venetian again.
Bottom line: Try XS instead.