I just bought the new Altima GXE 2000 with VOP and Convenience packages, and I after reviewing all the competition I can confidently say that the Altima provides the best value for the money.
My Altima cost me $16,000, which included the destination charge and all the options. A comparably equipped Camry or Accord would cost about $5K more. Even lower class Corolla or Civic would be a bit more expensive if comparably equipped. Still, Altima is bigger then the Corolla/Civic and is considered a family sedan rather than a compact. The reason it is so cheap is not the quality of the car, but rather the financial troubles that Nissan is in right now. This makes Nissan offer manufacturer's rebates on all cars. For example, I got a $1,400 rebate on mine. Plus, the Nissan dealers are all too happy to sell these cars even below the invoice price (they still get the 2-3% dealer holdback).
So, what do you get for this price? A very reliable, safe car (Nissan trademark), a 4 cylinder engine, all power locks and windows, air-conditioning, remote keyless entry, a good sound system (a tape/CD player comes in the Convenience package), and a host of small but important conveniences such as 60/40 folding rear sit and reading lights.
The only drawback is that it I wanted to get ABS breaks for safety (I live in the northeast and sometimes need to drive in the snow), but I could not find a dealer that had an Altima with ABS (even though it is one of the options listed). I was told that ABS are only installed on the more expensive cars, such as the Maxima.