Webwork - 12:10 pm on Jul 6, 2011 (gmt 0)
Hijacked? Not unless you have lost control of the admin and registrant functions of controlling the WhoIs record.
As to whatever Alexa is/might be doing that issue needs to be addressed by Alexa. (Besides, who really cares about Alexa these days . . when there are so many other sources of traffic, etc.? :-/)