I think Google is listening. I did a 3000+ word post last Christmas about the Google Account Problem. Now I’m pleased to report they’ve added Google Account Switching. I’m using it now, it works wonderfully, and it even works across Google Apps.
Thanks for listening, Google.
Equals Drummond 
Google are making some big underlying changes in Google Apps and building out the market place and apps store equivalent. The account switching is partially done, it currently does not work with Google Docs, there is also a limit on the number of accounts you can have open at anyone time to 3. Google Apps is being moved to the main Google Account platform as will which offers some additional benefits.
The Google apps administrator forum is excellent and so is the support
David, I quite agree it is getting much better – the account switch functionality solved a really big problem, and as soon as they have it across the full set of offerings, it will be excellent.