IPB is my weapon of choice when it comes to running a forum. I haven't looked back since I bought my own license about five years ago. They have always been ahead of the game when it comes down to comparing with VBulletin.

Even when comparing the change IPB did from 2.3.X to 3.0 was perfect. Clean frontend interface and a clean backend interface. I won't deny that occasionally I'll get confused with the backend here and there but nothing a quick search can't resolve.

VB just has nothing going for it straight out of the box. It does have a lot of great mod support, I'll give them that.. But nothing is intuitive with their product. Even with 4.0, they're still behind the times. I was turned off even more when they felt it necessary to but forth more energy into screwing over their customers with the licensing change, versus making their product something to give IPB a run for their money.

To each their own though :)