With so many problems in current Nokia E90 firmware, this is a very good news for every E90 owner!. Nokia have just updated the E90 "software updater" in preperation for a big firmware upgrade. Well, they have not yet released the firmware that will include the AGPS. The version 07.24.0.3 is still the current firmware, and the new version will be 07.38.0.2. As per allaboutsymbian.com the firmware will only come out in the first week of october..
The next firmware version will undoubtedly support A-GPS. In the firmware version 12 for the N95, this considerably reduced the lock time for the GPS receiver. New Nokia map has some good feature too. Unfortunatelly not many information I could get for this new firmware.
Jonmorris, my-symbian.com forum member have just returned from a London event with Nokia (where they launched the very impressive E51) and got speaking about the E90 firmware. The new firmware with A-GPS is now done, but it won't go out to the public for a couple of weeks. The only way to get it done at the moment is internally at Nokia. I presume this means they're still doing some final testing, but other improvements will be in the form of an updated version of QuickOffice.