when I check www.pagerank.net, one day I'll have like 400 backlinks and other times I only have 30....what gives??
It could be because the info is extracted from different data centers, which vary. But wouldn't have thought the variation would be that large.
Some datacenters can roll back to values before the last update. At some stage in the past you may have had 30 and they can roll back to 30 rather than 400. Its perfectly normal and the fact that it goes back up to 400 means you don't have anything to worry about.
oh phew, its just odd and scares me cause it took me awhile to get those backlinks....anyways thanks all for the replies!