Seconding Pioneer for head units. Not a fan of any of their other products, but their head units are top notch for the price. I can't comment too much on the new apps like Buffy was mentioning since I've been using my AVH 4200 for about 5 years, but these are the navigation units they have available right now:
http://www.pioneerelectronics.com/PU...GPS-Navigation
Personally I live in Hawaii and don't need navigation so I have no experience with those decks, but just look through and see which has the options you want. I don't know of any decks that have a blu-ray player, but if you want to retain the steering wheel controls you will typically need a separate module specific to your vehicle. I opted to not retain them because I didn't want to pay a few hundred dollars.