RULES for Complaining
1) Don't upgrade to 1.6 if you're gonna complain about the migration not working on your site.
2) Don't upgrade if you don't know what you're doing (you probably don't).
3) Don't upgrade yet until you get all your Extensions, Components and Plugins ready for upgrading. This means making sure they all are 1.6 ready. They are probably NOT all ready at this time (this WILL improve).
4) Test your upgrades before trying it on a live site. You should have been doing this for six months.
5) Make a backup of your site. Make another one just in case. Make a third if you're compulsive.
6) Upgrade once you and all your extras are ready. Not Before.
7) Don't complain about Joomla if the extension you can't live without isn't ready.

Preparing a new Template sucks, but take the time to do a site "refresh" with the latest styles and layouts.
9) Help Joomla migration by reporting specific problems to the appropriate bug chasers.
10) Be prepared to drop/abandon extras that are no longer needed, not current, abandoned BEFORE you upgrade. I would suggest you start paring them out now.
And when YOU are ready to do the migration it will be way smoother than if you try right now when YOU are not ready for Joomla 1.6. YOU have to be ready and Joomla 1.5 was good enough last week for you, it should be good enough this week for you. If you do EVERYTHING I suggested, and it doesn't work, then you can complain. Not until then.