The first time it happened to me I was just scrolling down my summary page using the slider on the right. I was about halfway down the page when suddenly the page changed on me. I can't remember what happened the second time but I don't think I was looking at products and was more likely to have been looking at my sold section or something similar.

A friend of mine emailed this morning to say it's happened to her a couple of times in the last two days, and it only happens on ebay, no other site.  Her son is a computer geek so it'll be interesting to see if I hear any more, but so far they think it's ebay doing it, or allowing it, which doesn't make much sense, but I think they mean that it's not something bad on my computer.