Backlinks from SBM considers by search engines. If they have Dofollow, then it will pass PR and if nofollow it just consider as backlinks. You can see them in Google webmaster tools and Yahoo.
SBM means social bookmark sites. As for backlinks, yes it is. But, there are very minimal value from it. Imagine how many links a social bookmark gives out a day? I suggest you to start other type of backlink creation as well instead of social bookmarks as these days social bookmarks is only best to get some instant traffic or to get our page indexed faster in search engines.
Yes, it is being counted by google or yahoo.........moreover it is beneficial for you for getting SERP, Traffic. Do not expect too much in terms of PR juice but sure it would help you more for optimisation. Keep Book marking with genuine short stories.
I did a load of social bookmarking months ago and no back links at all have appeared in yahoo site explorer or google. They were do follow as well.
well, not all links from SBM sites are indexed by google as backlinks, even though they are do follow and high PR. But I can say it still helps to get backlinks
No matter whether the links are from Social site or from forums/blog i just try to grab them which helps me for getting traffic
Yes it will be. Search Engine will consider your link as backlinks to your site. But don't stick on to Social Bookmarking only - use other link building strategies also for building backlinks. I suggest you to do Article Submission, Blog Commenting and Directory Submission.
yes they will be counted as back links. As those links get cached they will be shown in back links of your website. you can check back links through the tool backlinkwatch.com
SB sites are definitely useful for deep links. You will see some popping up in Google Alerts. As I mention often, diversify your link building with articles, blog entries, blog comments, PR releases, forum posts and social websites.
If they are dofollow links then it will pass your site some PR juice but if it's nofollow then it will count as backlink with no PR power