RJ47 is ethernet.
I guess more people value the internet now so naturally RJ is going to rise. ;)
edit: Oh. http://answers.yahoo.com/question/index?qid=20070313080701AA...
Based on the context, I'm not sure they even meant to say RJ45, since they mention Ethernet over USB elsewhere in the blurb.
edit: They explicitly say 10/100 RJ45 port later, so it's probably just a typo.
http://www.discount-low-voltage.com/Connectivity/Shielded-Pl...