Thank you bookgrl and WebyJ.
I had no idea it was 4 years of marriage for a permanent visa... I thought it was only 3. Shows how clueless I am. It seems like it would be a lot less hassle in the long run to just wait until then, especially with the rules changing, and that gives us a bit more time.
WebyJ, so if I were to wait until the 4 year mark (end of July 2010) and passed the test while visiting, it would be an automatic permanent residence without any further steps beyond that? Where do I go to arrange to take the test, and how soon after taking the test would I know that I've passed? (Or didn't pass, for that matter?)