So far my work with SP1 with a lot of AT programs has turned out to be .. well borring. Nothing exploded and nothing ate Vista for lunch. Oh sure it wasn't smooth as glass. But as far as the update goes it tends to be just another "run of the mill" sort of thing. Naturally I suggest you wait for the official "all clear" signal from you're software of choice. Or you can do that three month grace period on patches. However SP1 speeds things up, adds a few tweaks and is worth the upgrade once it goes online officially.
The Super Site for Windows has updated their FAQ for SP1. You can check it out at the link below.