Hello Tsadi,
Thank you for your input. There are a lot of factors that went into consideration before we decided to switch to vBulletin. The biggest factors are customer support and product development. While SMF has been solid the past 3 years, I can't help but think of the "what ifs". We were there when phpBB rose up only to die down and rise again. With our size and growth, we can't afford to wait for that to happen. For the past two weeks that I have been a vBulletin customer, support has been top-notch. This is something that even an SMF Charter member can't have. I love SMF and I will continue to plant communities with it. But for iSTORYA, I think it is now time for us to think about development security and customer support. On top of that, I have been looking for a sustainable SEO add-on for SMF for a long time now. Unfortunately, they all died down.
I will not worry too much about the backend. We will always put that on top of the priority list... and I am very much interested on taking a peek at your vB server.
Best Regards