For example, you've fixed the bug and spent four hours on it. Here is the list of actions you would normally perform after the bug fix:
With Subversion integration all you need to do is type short message when committing changes: "#75 status:fixed time:2 comm:there was problem in constructor". TargetProcess handles all the rest.
As a result, the revision will be attached to the bug with an ID of 75, the bug state will be changed to fixed, and a comment and spent time will be added. No further action on your part - just the one message on commit.