Comment 16 for bug 659143

My fix for this firmware loading issue:;a=commit;h=412b31334b831a8c2909afaca017c5a236ac2dd0
along with the the needed preparation patch:;a=commit;h=739fd9405416e22732e46a9226a8cac379bd57fc
is now available via the bleeding edge daily compat-wireless packages.

If you want to know as soon as possible whether this fix does fix your issue too you can compile that compat-wireless package. It is quite easy and takes only a few minutes. Of course you can also wait till the fix comes to you in even more user friendly form, but I do not know how long this will take.
Plus, the sooner you find out that it is not fixed for you, the more time there is to address that before natty comes out.

The long explanations for compat wireless are here:

That is the short version that works for me:
extract it with nautilus "extract here"
in a terminal window cd into the extracted directory compat-wireless-2010-12-14
$ ./scripts/driver-select rt2x00
$ make
disable networking via networkManager-applet
remove linux-backports-modules... if you have any installed. They might conflict.
$ sudo modprobe -rv rt2800pci
$ sudo modprobe -rv rt2860sta (if you have that loaded.)
$ sudo make install
$ sudo make unload
$ sudo modprobe -v rt2800pci
enable networking via networkManager-applet

If you can't unload the rt2860sta driver blacklist it and reboot.
If you have blacklisted the rt2... modules you have to undo that before you can load them with modprobe, of course.

Good luck :-)