I just got a MacBook Air and wanted it to use my Canon ImageClass MF4370dn printer. The printer is on my network with a static IP. I've no problem getting MacBook to find the printer either via Bonjour or TCP/IP, but I can't get it to give the duplexing options that are builtin.
Make sure you download the right thing. Canon's web site layout is horrible. You want the UFR II driver. If you download and install that, then go into the System Preferences and click Printers and Scanners. In the dialog that opens, click the + sign and IGNORE the printer if the OS detects it - you want to pick Add Printer or Scanner. From inside there, you can select the printer and the bottom most field Use: should show the Canon 4370dn - if not or if it says "Choose a Driver", the driver is not installed on your system correctly. Canon phone support is surprisingly good - if you did download and install the UFR II driver and if after going into system preferences and using the Add Printer dialog it still isn't working give them a call.
