I didn't see a link to this anywhere in the posts, but here is a KB artical that talks about this very issue.
http://communities.vmware.com/message/2162214
Might not make you feel better about it. I can tell you that I have noticed this behaivor in a number of VMware jobs where it will sit at a high percentage for a long period of time. One example would be removing snapshots, I have watched that job sit for about 3 hours at 95% on a job that took 4 hours to complete. Also talking with support on other issues they have told me not to pay attention to the % complete because it is not always an accurate representation of what the job is doing.