If you have links coming from an irrelevant, irreputable or unrecognized source, google don't count them as links. And even worse if your links are coming from link farms where you can actually get penalized for it. Quality backlinks are those from .gov, .edu and popular .com entities. Google have their own way of identifying this.
have many links from forums, articles, directories... And linkexchange.. So i really dont understand it.. on msn, yahoo and other im on 1000+ links..
google on purpose shows only a fraction of the links to your site. don't use google to check for backlinks.
Yes and best way is to chack like "domain.com" to get exact popularity of your site. by query like Link:domain.com it will show only fraction of links.
Ya same problem faced by me too.i have a few link backs(including that from forum signatures) but none is shown by G
Digitalpoint has a nice link tracker under the webmaster tools. Google likes to play shadowgames with webmasters and SEO's, so don't even try to get the link:domain to work on Google. Yahoo's works great. Also, I've heard in various places that Google only shows link from higher PR sites. I don't know what the cutoff is, but I'd imagine they aren't showing any links from sites less than a PR 4 or 5 at least. Anyhow yeah, shadowgames, Google, so don't waste your time checking links on Google.