Forums definitely helps SERP and traffic. Forums are one of the best ways to attract organic traffic.
Choosing the right keyword is very crucial. We have to find less competitive high traffic keywords. It can save lot of your money and time.
Best tool is Google adwords tool. Google has the largest share in search market. So google is the best source to get such analysis.
Submitting to directories will not generally help SEO or traffic. Yahoo and Dmoz directories are good for SEO and traffic. Most of other...
I think best combination is article marketing and press releases for SEO. For traffic forum posting is great.
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