prior to 27th february it was likely due to this bug in Sedo (counting everything that hit their servers as a page visit even though they didn't even show the page)
It shows that they've only filtered out a dozen or so filetypes so no doubt this issue is ongoing and shows sedo as having many more page views than is true.
-aqls-
from Sedo
Change in the way views are counted
01/27/06 | 17:01 | Bug Fixes
Better filtering of worthless calls to non-viewable file types Previuosly our visitor counting contained a small bug that registered some server calls as a visitor even when it was not an actual visitor to the page. For example, if a live website contained a call to download an mp3 file that was formerly hosted at a parked page, then the server call to retrieve that mp3 file would be counted as a visitor. We've now updated our visitor counting such that calls to nearly all such file types will be filtered out.
Previously filtered: css, jpg, gif, bmp, png, tif, ico
Filtered as of January 27, 2006: css, jpg, gif, bmp, png, tif, ico, zip, mp3, avi, rar, exe, mpg, swf, mpeg, dat
If one or more of your parked domains was receiving server calls for these file types, your statistics may show a decrease in views. However, this does not represent an actual decline in visitors, as server calls to these file types did not previously result in the browser displaying the parking page anyway.
By fixing this bug, the visitor counts displayed in Sedo traffic statistics will now be slightly more accurate (although the vast majority of domains will not be affected).