I have upgraded to version 5.0 and passed to vB
4.0 at the same time. After that all the tables (welcome message, categories, recent posts, recent reviews) were too long on the right. It is not aligned with the headers nor with the body color, which are the right width. The showproduct page is the only one that isn't too wide and is actually too narrow (about 70% of the defined width).
I am also using Photopost and do not have these problems there.