So, over the past few months I've been trying to come up with the answer of which form of backlinking is index quickest. From what I can tell this is the order 1. Direct Link Exchange (not recommended) 2. Blog Commenting 3. Directories 4. Forum Linking I don't know if that is correct but that is my experience, without pinging the link urls mind you, that's just on average from what I've experienced. What you guys think or what have you experienced?
From your list I would select forums and would add one; web 2.0 properties like Digg, Delicious etc. Good luck.
Most blogs with nofollow for the blog commenting, so this only can bring traffic to the targeted website. This is not good for SEO purposes because of the nofollow.
Have a full blown utilization of Social Media Platforms such as Facebook, Twitter, Reddit, StumbleUpon, Youtube, LinkedIn, and Photobucket among others.