Eclipse makes great headunits. Fujitsu Ten (Eclipse) makes the factory nav. units for Toyota so if you have steering wheel controls they will be plug and play.
This is their new 6620 for 08, replacing last years 6610.
Eclipse AVN6620 Navigation receiver with two DVD slots at Crutchfield.com
Pioneer and Kenwood have nav. units which are hard drive based as opposed to Eclipse's DVD based navs., but Eclipse's are still very nice units.
If you like Kenwoods, take a look at their new 08 line up. The 8120 which is what alot of us are waiting for, or the 7120 and 5120 also.