There are new reports surfacing of a bug in Google Webmaster Tools, where the links report is showing a small fraction of the links it was reporting the previous day.
Webmasters are reporting 80% to 60% drops in backlinks counts as reported by Google Webmaster Tools today versus yesterday. Personally, I see exactly the same number of links from when I snapped a screen shot a few days ago. But maybe I am unaffected or maybe the bug is rolling out more widely or maybe it is fixed already?
One webmaster said:
Hi just entered Google Webmaster Tools and I saw I lost today about 80% of my backlinks.
I too lost 80% of my backlinks today in WMT but there was no change in traffic so hopefully this is just a temporary bug.
It is not uncommon for there to be bugs with this report. We reported a similar bug in February of this year and then several times before.
I assume this is just a bug and you do not have to worry.