This is an interesting question. I think Google updates the report on a regular basis (lets say every 15 minutes), the "problem" is that it seem that the results are continuosly re-evaluating.
I have seen reports that I had X Clicks and earned Y Dollars. Two hours later the clicks and the dollars dissappeared.
It seems that google runs corrections and re-write the results. Thus it is useful to wait some time to see the "real" results.
Google Adsense reports
Linear Mode
