As a caveat: Both sites I'm presenting here are relatively new and untried. You're getting in on a ground floor, but we can't promise fame and fortune from them (yet).
While not technically a PUG-finding tool, ArenaArc helps you find Arena teams that meet your server/size need. It's not quite got the robust toolkit of Arena Junkies but for folks who are just getting started in Season 4, ArenaArc is a decent place to look for some fellow soon-to-be-Gladiators on your server. There's at least a few people on the forums who already seem to like it.
Pug-O-Matic gets to the heart of it -- finding a PUG. Of course, I'd argue if you're hitting up a website to put together a group, that group's not really a "Pickup" group anymore. Still, the idea's sound. I had a little trouble figuring out the tool at first, but I later realized I couldn't find anything because not many are using it yet. I guess we'll see if it turns into something.
So, those are two new offline LFG channels. If folks use them, I'm pretty sure both will turn out to be helpful. But if neither catches the interest or zeitgeist of Internet-cruising WoW players...well, you can't use a social network if folks don't network into it.