WEB 2.0 works good now, compared with all. You need to diversify your links, if you have only one type of links coming to your site it will get penalty by google, it looks suspicious.
So, mix the link sources. When ever you going to get backlink directly to you money site spend few seconds researching the source of the site. Make sure that site is not affected by any updates in the past, how many OBL that page/site has, the website is your niche relevant, etc.,
If you have money then make use of guest blogging and press releases. It will drive traffic and also gives you a backlink.