Google had a policy update, as you can see here. But the biggest change of all is that the old competitive ad policy which read like this: is now gone. Following up on that revealed that using similar looking ad services like YPN is still prohibited (beside the fact that it's forbidden by YPN terms). But other contextual advertising like IntelliTXT and others is allowed.
I'm afraid the above post is wrong - although that quote has been removed from the program policies summary, the following is still clearly stated in para 2 of the Google AdSense Online Standard Terms and Conditions: "General. You agree not to display on the same Web page in connection with which any Ad Unit, Ad, Link, Search Box, or Referral Button is displayed (a "Serviced Page") any advertisement(s) that an end user of Your Site(s) would reasonably confuse with a Google advertisement or otherwise associate with Google. If You have elected to receive content or Site-based Ads, You further agree not to display on any Serviced Page any non-Google content-targeted advertisement(s). If You have elected to receive Search Results on any Site(s), You agree that Google will be the exclusive provider of Internet search services on such Site(s). Certain Google services available as part of the Program may contain filtering capability, such as SafeSearch or AdSafe, that You may access through Your account. However, if You elect to enable any such filters, You acknowledge and agree that: (i) it is Your responsibility to enable such features in accordance with the specifications provided by Google, and (ii) Google does not and cannot commit that all results (including Ads, Links and Search Results) will be limited to results elected by enabling such filter(s). Google may also include in certain services features which are unsupported under Google's then current technical documentation. Such features are provided "as is" and Your use of them shall be undertaken solely at Your own risk."
See this link: here You are allowed adsense and adbrite. I think the only thing you can't do is ads that read the content on the site and display ads. (I think). Keep your ads dis similiar to adsense ones and you'll be fine.
Adsense is "contextual" as in the advertisements are based on page content. Adbrite is not contextual because the ads are not based on page content, its more like a direct advertising system.
According to last reports, this change has been decided on already and they are only in the process of updating their different documentation. The link kiplarson provided is a good source about his issue.
you can now display adsense and another contextual based advertising system on the same page, You’re welcome to display Google ads on the same site or page as other third party advertisements provided that the formatting or colors of the third party ads is different enough from that of the Google ads. In other words, if you choose to place non-Google ads on the same site or page as Google ads, it should always be clear to the user that the ads are served by different advertising networks and that the non-Google ads have no association with Google. If the formats are naturally similar, we ask that you choose different color schemes for the competing ads. Our intent with this policy is to be as fair to our advertisers as possible and to maintain the integrity of the AdWords and AdSense programs. You can learn more about this, and all our policies, on our program policies page. I got that straight from the Adsense Website Here I wrote about it on my blog, SEO rants
There is a lot more too it than "Being permitted" There is actually more to it than Jensense has covered, for instance you can't place Chitika minimals next to an adsense rectangle http://andybeard.eu/2007/01/adsense-guidelines-contextual-ads-adsense-backgrounds.html
AdBrite has never been an issue because they aren't contextual. You'll notice that pretty much all AdBrite network ads are finance related - even if they are displayed on a children's site about play-dough modelling! I'm sure Jensense's information, that G are going to revise this rule, is absolutely correct - HOWEVER, until it appears in writing I would discourage anyone from risking it. Even if Joe Bloggs from AdSense Support says it's okay do you think that will stop Jane Doe from AdSense Support from banning you because she is following the written letter of the law? - I don't think so! Until the written rules have actually changed I'd not risk listening to hear say and conjecture.
I just noticed a typo in what I wrote and corrected it. What you do is implement and then ask. They are not going to ban you, but why waste your time implementing something that is based on old rules. Adsense have said that the policy are the current working set of ToC, but of course CYA always applies
CYA? (still new around these parts) I'm pretty sure that no other advertisers were allowed except like referral links. I know that commission junction was not allowed before the update, so why would Adbrite be allowed before the update? Also, I thought these rules were already changed (in writing). Correct me if I'm wrong.
Why is nothing ever straight forward with AdSense? Half the program policies have been changed, but the Standard Terms and Conditions, to which I linked before, still remain the same that "You further agree not to display on any Serviced Page any non-Google content-targeted advertisement(s)". Correct me if I'm wrong but there's still a contradiction in these rules - rules with contradictions are worthless. Let's hope they get them sorted pronto!
I'm going to email them again, and then refer to the various websites that have posted on the subject (i.e. jensense) and see if what they've said is true. lol, and as for the CYA (I've never used that abbreviation lol, thought it was some sort of an abbreviation that is business related i.e. CTR)