I think the easiest way to sum up Star Wars: The Old Republic (SWTOR) is like so:
Take Knights of the Old Republic, increase the amount of content by an order of magnitude, add repeatable dungeons, PvP, and the ability to play with your friends, and the result is SWTOR.
This is not a bad thing. If the comparison is meaningless because you've never played Knights of the Old Republic (KotOR), you should. It's getting a little creaky, but it's still a very fun RPG that drips with the essence of Star Wars. A lot of the stories and characters in SWTOR will make more sense if you've played KotOR.
I think SWTOR is possibly the best game Bioware has ever made, and I've played every RPG they've made. I've seen plenty of blog posts and reviews out there saying the game sucks, though most of the complaints boil down to "this is not the game for me" rather than "there is something fundamentally wrong with this game".
If you like Bioware RPGs and you liked WoW, SWTOR has a lot to offer you. If you can't stand the style and gameplay methods used by either of those, then the latest Star Wars game simply isn't going to be for you.