For those of us who use the Ethereal packet sniffer, it's now named
Wireshark. Spinning-off the product with a new name was evidently the result of a trademark conflict between the creator of Ethereal and the owner of the Ethereal trademark itself. More on this here here:
http://trends.newsforge.com/article.pl?sid=06/06/09/1349255&from=rss
The latest release of Wireshark (0.99.2) is available from:
http://www.wireshark.org/
Ethereal is still available from
http://www.ethereal.com/. However, with the entire Ethereal development team moving to Wireshark, I am not sure if there will be any future releases of Ethereal.
If you don't know much about packet sniffers, check out
Packet School 101:
http://www.chrissanders.org/?p=47