Hello - I have seen today that the impressions total has gone up 3 times normal and I can not see any change in my normal stats, so I dont think I have more visitors, have they made a mistake or is it maybe that they will 100% now ad space.
Simple answer to this is to check your Full rate percentages. If you had a 20% full rate yesturday and a 60% full rate today then that simply answers your question.
I had the same problem for Feb 6th and partly Feb 7th, my traffic was nowhere near the stats. I am still waiting on reply from support on that issue