google analytics?
 

I've noticed past few days, I get odd day where analytics shows a weird spike in direct traffic only, yet no increase in any other traffic. This only happens for same two sites. Yet my whos online counter does not show any difference. These are wordpress blogs

anyone else notice this error?

Its not an error..
Add network domain as second dimension and you'll see its Bing crawling/abusing your site and executing javascript.. But somehow G'anal doesn't filter this out as being bot traffic.

anyway to stop it?

If you don't want Bing & Yahoo traffic, add this to your robots.txt file.