Thanks for the info.. In my opinion, signatures are useful and can be considered as Do Follow links..
Funny, because the ad link - "Links" on your post is set to no follow. <a href="http://ads.digitalpoint.com/go.php?k=Links" rel="nofollow" class="inlinead" target="_blank">Links</a> Code (markup):
Google likes natural links or links that at least look natural. Directories, Blog comments don't matter much. 2 P6 links will be given less preferrence as compared to 3 pr3 link 5 pr2 links and 9 pr1 links because that is how natural links grow when you are not doing SEO yourself
I think in future google may stop giving importance to the forum signature and blog commenting links because every one know about this easy way of creating backlinks. any one having time or manpower can develop a huge number of these easy links without creating good contents. This is a smart way to affect the google's result for a aggressive marketer
You can't go wrong by keeping your own blogs, writing articles and PR releases and also keeping fresh and keyword heavy content on your site.
Google loves links from big sites. I had a post go viral on StumbleUpon and that was enough for my post about two fun facebook tricks to go to #3 in Google for the search "facebook tricks" StumbleUpon can be an awesome way to get a high PR link that can jolt your PR, if you have ADD friendly content that will stumble well.
Yeah but if you know the right stuff to do and have all the "equipment" blog/forum posting for you site can be AMAZING! I have done it to a few of my sites, but right now I am seeing what will happen when I do "ALL NATUR-AL" with the site in my siggy.
Most blogs make comments no follow by default. It is getting hard to find one that isn't no follow so I think you will see comments make a come back as the spam stops. Wordpress mu is a good way to get links. You can create a sub domain of the origional site and share the links with the owner of the domain. If your interested check out http://top5free.com/
blog comments and forum signatures count to google, not as much as a regular link, but they do help your site in a small percentage.
Blog commenting and forum signature only helps the new site but one can't rely only on these in long term