Well, here's the rub. It largely depends on how your apache is configured (more specifically: WHO it is configured to run as)
Any files/folders that are created "programmatically" will be owned by the Apache account.
So, for instance, in your case (and mine), I'm one user and my apache server runs as "apache". Stuff I put there, like the original install, is owned by me. Stuff created along the way via plugins or just normal WP operations like /cache, is owned by Apache.
In my case, no big deal -- I also can su as root and chown files when I need to modify them. If you're in a hosted environment you likely don't have that luxury. ;-)
I think, and have no practical experience with it, that apache can be configured via suexec to run as you which would then have all those programmatically created things be owned by you. Again, I've not messed with it, but here's a link for more info: http://httpd.apache.org/docs/2.0/suexec.html