How would a web site control whether users run ad-blockers on their clients? Believe me, if they could stop it they surely would.
I don't believe this problem is caused by an ad as such, especially as it only affects my iPad, not other browsers. It's a layour problem with some component that is meant to be invisible - for some reason it isn't in the iPad browser.
The same thing is happening on the companion Computing.net forums so it appears to be something that has changed site wide in the past few days. Ah well, I'll just give Tom's Hardware and Computing.net a miss on the iPad for the time being.