you can't switch to IPB. All of the links indexed in google will 404, because it will be an almost impossible task to get them to mod-rewrite properly with the new completely different system. That reason alone is reason enough to give up on IPB.
Leave it on VB3 tbh. VB4 brings nothing that cant already be coded. Other changes are negligible or insignificant.
Leave it on VB3 tbh. VB4 brings nothing that cant already be coded. Other changes are negligible or insignificant.