Hi,
If the iPhone is not recognized after updating iTunes 8.2, try the general troubleshooting tips in one of the articles below:
If you have a PC, take a look at this article:
http://support.apple.com/kb/TS1495
If you have a Mac, take a look at this article:
http://support.apple.com/kb/TS1591
Also make sure the iPhone is directly connected to a high-speed USB2 port on the computer, using the cable that came with it.
-Jason