Hmm. I have played EQ 1, EQ 2, SWG, FFXI (briefly), CoH, WoW and now Guild Wars (not including a bunch I beta tested or did a free trial of and didn't like).
Here is my opinion, for what it is worth. Have you ever seen the movie
Full Metal Jacket? The first half of that film is one of my all time favorite movies. The second half of that movie sucked. You could not even tell that the second half of the movie was made by the same director.
That is how I felt when I played World of Warcraft. From level 1-59 I loved that game. I have only played one other MMO I liked better, which was EQ 1. WoW is simply a fantastic game from 1-59. Then you reach level 60 and move into the sucky half.
So, will GW be better than 1-59 WoW? No. Will it be better than 60+ WoW? Absolutely. Will it have better PvP? Absolutely. Will it have more exciting and fun things added to it for you to enjoy at regular intervals? Absolutely.
One word of caution though. If you think there are a ton of idiots running around WoW, you ain't seen nothing yet.

Free games lower the barriers to entry. When I logged onto the beta weekend I was awash in a sea of characters obviously named by children or people with a
Porky's level of maturity. However, unlike WoW, in this game you can turn off local chat (which basically makes your character deaf and you don't have to listen to them) and it's all instanced so you can avoid them for the most part if you want.