calumniate - 6:57 pm on Oct 13, 2006 (gmt 0)

Big Dave made some good comments. There is no way to become an 'authority' really. But strong deep links, age and content built up will make it so it would be pretty hard for you to change your ranking drastically with minor changes.

So I think once these factors play in heavily enough, you can make changes to your website whenever you feel like it and your SER won't ever really change.