iFrame is a HTML tag that enables we to include files from anywhere on the web, onto any particular page.
one thing i know is technorati uses google adsense on there ad block. so if you have your adsense 3 block on page and technorati ad blocks in page, some times all will show google ads. see my site http://www.techwacky.com, i sometimes get adsense from technorati media also, first i was like wtf, later after many research found that they are google ad partner.
Of course it is, premium AdSense accounts exists, but not for us, the so called "small players". Only big fish on the Internet can get premium AdSense account, in fact, you don't get it, AdSense offers this to you by itself, when you reach enogh popularity...
I mention above site articles pages only show 4 Adsense unites. There home page not display 4 Ads unites.
Ya i also view that that web site sometimes display "technorati media" ads. So sometime that is the reason display more than 3 ads in same page.
I have 4 AdSense units on my posts not a premium but I have a partnership with a network who has one - http://www.cravingtech.com/more-google-adsense-formats.html So I have - 1 on top of posts using the Premium format - 2 at the bottom of the posts - 1 on top of my sidebar Should I remove one of them? *scared now*