I have never heard of this, but when trying to stumble some articles on my blog today I fill out the info, hit submit and then just get a blank box instead of the box where it says "rating submitted". I tried stumbling a page on a different site and it worked like a charm, then went back to the blog and tried another page and got the same result. This has been happening all day now?
Yes it is possible .. like http://forums.digitalpoint.com is banned its because of going against thr TOS !