Looking to get Youtube-quality video stabilization from a software based video editing application (on mac)
A coworker has just turned me on to using Warp Stabilizer. It's a built-in effect in Adobe Premiere CS6. Before using this tool, I also used After Effects to smooth and stabilize motion.

The difference is outstanding. Warp Stabilizer has worked faster, within my workflow, and more reliable than After Effects stabilization has. This has been huge for me. Here's a quick guide that outlines the effect: http://www.premiumbeat.com/blog/premiere-pro-warp-stabilizer/

Another solution is Lock and Load. I've never used it, but I've heard it gets the job done. Might be worth looking into if you do not already own the Adobe Creative Suite. http://www.coremelt.com/products/lock-and-load-x.html