Apple has released Java for Mac OS X 10.6 Update 2 for Snow Leopard users, updating Mac OS X's Java SE 6 to 1.6.0_20 and delivering "improved reliability, security, and compatibility for Java SE 6." The only details given revolve around security fixes, so it's probably worth downloading this update even if you don't anticipate using Java applets much. The update requires Mac OS X 10.6.3. (Free, 78 MB)
Viewing Wi-Fi Details in Snow Leopard
In Snow Leopard, hold down the Option key before clicking the AirPort menu. Doing so reveals additional technical details including which standards, speeds, and frequencies you're using to connect, as well as what's in use by other networks. With the Option key held down and with a network already joined, the AirPort menu reveals seven pieces of information: the PHY Mode, the MAC (Media Access Control) address, the channel and band in use, the security method that's in use, the RSSI (Received Signal Strength Indication) measurement, the transmit rate, and the MCS Index. In Leopard, some, but not all, of these details are revealed by Option-clicking the AirPort menu.