Well, first of all, Both, blog commenting & forum profiles/signatures work (IF used properly). The key to a successful community link campaign is that you contribute to the community in a way that others find helpful. If all you are going to do is 1 line posts on blogs or forums then don't waste your time, more than likely your posts will get deleted anyways.

Ideally you want both the do-follow backlink PLUS the referral foot traffic the sites visitors has to offer in order to maximize your potential. This means that you should take the time on each of your posts to genuinely assist and or contribute to the forum thread or blog article topic in question. Well thought out posts normally stick, meaning the mods / blog owner felt it was contributing & decided to keep it. The more on topic your post is, the more curious viewers get about you and may decide to visit the site in your post / profile / sig area. One liner posts normally get skipped over by viewers & they miss out on all the potential referral traffic.

Also, Keep in mind, that it's always best to try & get unique IP server (website) backlinks. The more backlinks with the same anchor text you get on the same site, the lower the value per link drops. Ideally you want most your links to be coming from different IP's, Most times, each server a host uses to host websites has a different IP assigned to it. Some hosts may put anywhere from 5 to 5,000 websites on 1 shared server (All will have the same ip).

Personally, I would much rather have 1 backlink on 10 different websites with unique ip's, than 10 backlinks on 1 website. It's all about strategy though really. I mean, STOP spam tactics NOW!!! Using spammy tactics just makes you look bad and can lead to bad reviews, spam reports to your host, Accounts being banned, posts deleted, etc... Sadly we are in a time where 7 out of every 10 posts that only have 1 line or less of text can be classified as spam.

Because of spammers, I become more and more hesitant about sharing new ideas and techniques. As I always find someone trying to manipulate and abuse them. Like anything in life, once lots of people abuse and manipulate something, the company / service being manipulated changes the way it operates to compensate & make business 10 times harder for the honest people. Sad how that works. How 1 bad apple has a tendency of rotting a whole barrel of apples.

I see forums now days that are requiring 50 to 100+ posts before a sig link is activated due to spammers. And i can't blame them for it, the spammers forced them to take action.

Hope that helps a little.

I have to ask, where have you been for the past two years?

Just do a search for "profile links" and "angelas links" and you will have a ton of reading to do.