I am a frequent Adsense report checker. I have always felt that Google updates my reports about every hour. Today, I seem to be seeing more frequent updates, maybe every 1/2 hour. How about you? How often do you feel that your Adsense reports are updated (usually)? Real time, plus how many minutes? I am 45 miles from Google headquarters, if that might be a factor. If only it were 30 seconds. Then I could REALLY drive myself nuts! Ha-ha-hah!
I am certifiably insane, and if you are too, you will enjoy this little tip: Want an AdSense stat update? Change your Date Range and hit the <Report> button again. Voila! A stats update! Change back and you'll see that the stats in the old range still haven't updated -- it's spooky.
Or, if you just want to point and clidk...today, this month, all time are usually at different points in the updating cycle. Plus, for people who like to stay up late, the end of the day stats are usually updated one more time about 12:30 your time... Madness! But fun when your site is on a bit of a run.
It varries here. Sometime every half an hour and then every one hour or more. Though checking daterange is not live for updates, it reports new stats earlier then todays stats.