Remove immediately. It and MacDefender are two of the best documented "viruses that masquerade as software" to be found.
There are some big differences between the two, although the advice to avoid is certainly appropriate. The MacDefender series were deemed Trojans by the AV world and apparently came from some crooks that have since been arrested for some part of that scheme.
MacKeeper is not at all a bug, virus or even malware, though I think it might qualify as a Potentially Unwanted Application (PUA) judging from all the complaints.
Although the ZeoBIT developer does have a Russian office, they are located in Sunnyvale, CA, a few miles from my house and they had one of the largest booths at Macworld|iWorld San Francisco last week. By far the most booth bimbo's of any vendor I've seen in years.
Talked via email to my Machero...MacDaddy here in Seattle. He said it may or may not be Malware ie it may or may not be harmful but he has heard it seems to trigger bad things with other programs that I may already have installed. So, for example, those PC applications that are already not mac made...they may start hiccuping. So I think I will remove it asap. I will try the links from MadMacs and see if I can figure out the uninstall. Love this forum, thanks so much.