There's a few services around now which offer text link ads within an existing network of content, but the question is, how long do those backlinks need to remain present and active before it can be safely assumed that Google and the search engines have taken that backlink into account? Is it 1 month, 3 months or more? 6-9 months maybe? Since these are paid for links, nobody wants to be overpaying each month more than is necessary, so what would be the minimum recommended time to keep those links active? Any reasoning to support your views is also appreciated. Would the removal of those backlinks after the period negatively affect the rankings of the site being linked? How is that normally seen? While it is understood that permanent backlinks are the best, but it would be interesting to know how significant the effects are of removing those temporary backlinks.
The main advantage of temporary link is to boost your site WHILE you build up more permanent links to your site. A temporary link improves your rank temporarily, so the next time google spiders you link provider and doesn't see it, he's going to take that in consideration and just as you don't get up in PR overnight you don't go down overnight too. 1 month is useless 6-9 month ok, 1 year better.
Thanks for your comments, it makes sense. For a new site, it is a nice method of building links quickly on a temporary basis, while using the time to build more quality permanent links. Since each link can cost something between $10, $15, $20 a month on a blog post page that has about PR2-3, would you say it is a good deal? I am assuming a good time period would be to keep the links active for about 7 months, so that is $70-$140 right there per link. Is that good value, or could the money be better spent elsewhere?
I think 6 months would definitely be long enough for your link to be indexed a couple of times, but that price range is a little steep. I think you could easily find sites that would sell you an annual PR 3 link on an annual basis.