Chris and some others did the original port to vBulletin of ibProArcade by wrapping everything around so that the code still thinks it is an Invision-Board. They just "translated" the variables.
I was involved in the conversion and had contact to Chris to help out with some things, that's why I am administrator at ibproarcade-vb.com but the main work was not done by me.
Now I took that vBulletin-Version of ibProArcade some time ago, fixed the security-bugs and alot of other bugs and malfunctions to make this arcade fit my personal taste of a "perfect" hack. I improved the style alot, included most AddOns (AllMods from stlmike) and finally made one complete version which automatically detects wheather it's vBulletin 3.0.x or 3.5.0 and sets all necesarry variables in a correct way. This is working for about 2 weeks now and means that upgrading to vBulletin 3.5.0 just needs to import and active one single plugin and the ibProArcade continues its work in your forum
Now that this license-problem came up (two php-files in AdminCP are from the original Invision-Board) I had to stop my planned of my ibProArcade release last week and started re-coding the whole AdminCP-script for the ibProArcade. After finishing this I can (finally) release it and thus bring up a legal, complete, extended and bugfixed version of ibProArcade for vBulletin *proud*
Chris already gave his permission to release it (thx!) so just five me some more days to work on the AdminCP-script.
For all german users one more good news: this ibProArcade-Release will contain a complete german translation
About ibProArcade 3.0: I personally won't start converting this to vBulletin, I think Chris can do this much quicker. But if you compare v3.0 to my upcoming version it already has alot (maybe all ?) feature of v3.0 so I think there will be no need to quickly upgrade... But time will see