All backlinks help to some degree.
But, backlinks on forums don't have as much juice as other backlinks.
Backlinks from LOCAL directories and LOCAL group memberships such as the BBB have much more power to get your site to the top.
Google is now looking for local relavency and Google will give your site higher web cred for it.
Google is changing (they are always changing) to fight people that were gaming the system.
Also, get a few reviews a month from Angies list, Judys book, Brown book and Google Reviews.
Start building your Local web cred now!!
Check your backlinks here:
http://www.backlinkfinder.com/
or:
http://www.searchenginegenie.com/backlink-checker.html
They will tell you out of all those links how many show up on Google.
You may be surprized!!