This is the current Color LaserJet Printer I am recommending. It does duplex printing (double sided), has networking and starts at $399. So far, this is a decent entry level printer.
Note: Do not use the PS drive. This driver has caused PDF's not to print and also goes through the action of printing double sided when you only print one page. Very annoying.
Use the PCL6 driver. for full, annoying printer functionality.
This functionality has only been tested on Windows 7, 64bit thus far.
Here is a quick video review and demo.
http://chris.pirillo.com/hp-color-laserjet-cp2020-review/enjoy,
Jon