There are two separate reports from two different threads that Microsoft adCenter's conversion tracking is inflating their figures.
First, what is adCenter conversion tracking?
The adCenter Conversion Tracking help says:
Converson tracking is a free feature provided by Microsoft adCenter to allow you, the advertiser, to identify how many actual conversions result from users clicking on your ads.
What are the requirements?
So why are tech savvy webmasters reporting that Microsoft is inflating these numbers by 50% and more?
PPC at Search Engine Watch Forums says "their conversion stats they are providing us are inflated by about 50%! Some days I'll see a term with one single click and four conversions!"
Natekapi at DigitalPoint Forums says "the conversions are obviously off because it told me I had 10 in 1 day, when I really only had 1 conversion from AdCenter."