Xenforo is the most open and developer friendly community I have ever seen when it comes to developing a community. It is unbelieable how great this community is and how charitable you guys are. I haven't seen such high quality add-ons that were paid yet alone free in Invision Power Board 3 or 4. This is just amazing, you guys are a great community. This is something money can't buy.
I have used myBB and SMF as well - this is like IPB and myBB had a kid.