Ranking drop - Google update or single blogroll?

I noticed today that 3 of my website's have dropped off serps (and 1 before penalized site came back up). Is there a some kind of update going on?

Other reason, but seems rather quick from google, would be dance, since yesterday I added quite strong image sidebar links from relevant sites to all of these sites today moved a lot. Majestic stats for those sites I got backlink fr were Trust 25-35, Citation 35-50. Can single blogroll cause dance so fast?

If you recently added some links, you're going to see some ranking changes. Wait it out for a week then check your rankings again.

IMO - NO. This shouldnt be the case.