I do not understand why but I had Pagerank 2 after last update and week ago... it's just gone url: http://www.gamesterstalk.com why? I am still getting some traffic from google, so I don't think that I am banned ?
it's because google think they can't trust you with PR. Either because you buy links to increase PR or you sell links to people who want to increase PR.
Maybe your PR toolbar is just hitting a different datacenter that never got the update, or something. Try checking it with one of the good PR checking tools see what it tells you.
doesn't matter because link exchange is allowed with google. Google dropped the PR for many many websites ... it's a pity your website got powned by google. I myself have a PR 4 website and 3 website with a page rank of 2 ... and my PR stayed the same
Excessive link exchange can lead your way to penalization. But I'm not sure if your problem is related to excessive link exchange.
Another thing, don't do massive link exchanges with sites that are unrelated to your site. Massive link exchanges to unrelated sites will look like you're trying to best Google's algorithm to get your PR. If you must do link exchanges, do so with QUALITY sites--related sites. Check whether those sites are still linking to you. Check the anchor tags they use to link to you, they might have placed a rel="nofollow" tag. That means you're leaking PR to them, but not vice versa. Then check the sites you're linking to. Type their addresses in Google. If they are banned, you should remove your links to them immediately!
Either you are checking on different datacenter, or Google might think you bought links from other sites.
I know one possible reason: The links at the footer are all dofollow [i.e. "poker", etc.] and Google mistakes them for paid links that pass PR. Make them nofollow and submit a reinclusion request.
May there are many irrelevant links or you paid to get high PR links. By the PR doesn't matter for getting high SERPs....
Moreover chances there the backlinks you were getting has been devalued or too lost rank. try to get more backlinks if that is in your case.
I think just a 3link trades wouldn't harm your site not unless you trade link with a site with bad neighborhood,. Anyway, when doing link trades avoid excessive linking as google is tired of this one