I'm not the only person using this spec (siphon life/felguard leading to SM/FG at 79), I'm not claiming to be some unique snowflake!
But I made a video to show my friends the sheer power of all the WotLK changes (not just talent additions) that combine to make a pretty kickass leveling spec (I've tried them all, and this one blew the others away):
http://warcraftmovies.com/movieview.php?id=89547
It's narrated by me (yes, that's me, yes, girls do play WoW, yes, we are in raid guilds!) and I really had a blast making it. I filmed on and off from about 73 to 79, and then had fun picking interesting snippets to fit into a 4-minute video.
I even picked my favorite elite to show the spec doing well soloing group quests.
It's not complete without a nod to Gobo of <Vendetta>, whose TBC movie with a healer gave me the idea of making this movie -- without a healer of course, since we don't need one now.
** WARNING: There's WotLK spoilers. If you don't want to see quests, XP grinding areas, mobs, etc., then don't watch. **
I got good reviews from my friends, so figured I'd throw it up on warcraftmovies and link it here as well. I hope it inspires at least one other person to give it a shot and break out of the "I will level destro!" or "I will level affliction!" mindset and go with a solid two-tree build.
If nothing else there's few things more fun than taking on an entire camp. And living.
Some of the stuff on the video may not be as clear as I'd like, like the talent trees, so I also wrote up an article about it. The page also has some tips that I couldn't figure out how to fit into the video well:
http://strats.fusion-guild.org/index...kLevelingWotLK
It explains, for example, why I think this spec is stronger than a more traditional leveling spec of deep affliction would be.
(this is a duplicate of my WoW forums post, apologies to anyone who has to sit through it twice!)