I received an anonymous email stating that beginning December 1st, the Nikon D90 will get a buffer upgrade that will cost around $30. The upgrade will allow 5 minutes of 1080 resolution HD video. It will also have upgraded firmware that will allow the new MP-7 microphone (?) to be plugged in via the USB port and get activated in the camera. A new microphone adapter to plug in any microphone will be also available.
If this was an $300 upgrade for the D700 (especially the microphone part), I would probably believe it, but for the D90? I don't know... What do you think?