I have several Access 2007 database published to my sharepoint sites which work well but can be slow ... sometimes very slow. I use 3 different hosted sharepoint sites and find that the best one provides good response while the worst one ranges from ok to very sluggish. Doing nothing more than installing Access 2010 and opening the same databases improves performance greatly with databases from all three sharepoint sites. This is surprising as none of these sites have upgraded to Sharepoint 2010. Any thoughts on database performance improvement using a Sharepoint / Access database???