LinkedIn had 650,000 email addresses and passwords stolen. If you have a LinkedIn account, ScalIT strongly suggests changing your password as soon as possible to a unique and secure new password (upper and lower case letters, include numbers and symbols, too; make at least 8 characters). Many of these passwords have already been published on hacker sites. If you have used the same password that you used on LinkedIn on other sites, you should probably consider logging into those sites, too, and changing your passwords there.

http://www.informationweek.com/news/security/attacks/240001674

At ScalIT, we are always concerned about our customers security.