Website running on different databases

My website is currently running with 3 different databases. My application connects to them each with a different user.
eg. My forum is one db, and my image gallery another.
All DB’s are on the same host and server instance.

Since I’m currently redesigning some things, I was wondering if it would be better to create one user for all of them, or put all tables in the same database?

My application is such that a gallery block is sometimes used on forum pages and such, so that 2 or more DB’s are queried for one page request.

Should I merge my db’s for performance / to reduce connections or won’t that be worth the effort?

In MySQL, databases are basically just namespaces. There’s no performance benefit from putting tables in one database or many, not for little databases like your website’s. It’d be great if one user had permission to access all 3, as then you’d only need one connection, but you don’t have to combine the databases to do that.

Thanks Dan, I know what to do next