If I'm not running rtmpsuck (and not using iptables for routing), I can view as many streams as I want. If I am running it, I can run multiple at a time, but it only records the first one it picks up.
The websites I've tried:
http://rt.com/on-air/
http://www.ustream.tv/new
http://www.hulu.com/
http://www.myfreecams.com (which actually will only load one stream at a time, and must be the one rtmpsuck is recording first to even show in the browser)
I'm also using rtmpsuck 2.3 because when I've tried to compile 2.4 from git or svn, I get segfaults from rtmpsuck and rtmpsrv.
Side question: Is there a way to not overwrite files by default in 2.3? I see a patch for it in 2.4, but like I said, segfaults.