Unfortunately, any sort of animation tends to bug me - I'm just a pain in the ass like that.
However, if those switches and fades happened every 30-60 seconds* or so, I think that would be fine. A fade taking between 2 and 5 seconds say, I think would look best. I'd really have to see it to tell you properly though.
*It might actually be less distracting if that time were varied between ads too, otherwise the mind becomes very used to expecting movement at that set interval and it becomes even more distracting.
How about you set up a test page with a poll and let us all give you feedback on it? (I'll remember to turn off the ad blocker.
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