Opt-In Target emails ? Viable option ? Other options ?

[Niteblade]

I realize that most forums get big because of organic (natural) growth based up quality content as well as quality members interacting with one another. There really is no way to "jump start" this organic process (it takes weeks and months for a community to evolve naturally) -- and most experienced people people recommend AGAINST spending money to circumvent this process.

With that being said and understood:

• What are people's opinions on using opt-in email advertising ?
• Will google punish those who use this method ?

Everyone knows about the successful marketing techniques such as:

• Using myspace to advertise
• Using signatures in forums to advertise -- when allowed
• Using a link exchange program of some type -- "Display my banner and I'll display yours.."
• Posting in a link directory
• Creating unique content, such as articles, and publishing them to a blog that references the forum.
• Creating a unique article and submitting the article to free article publishing sites -- be sure to reference your site in your article

Thanks!