Ads on websites are a bit of a touchy subject. Sites do need money to stay ‘alive’ and advertising (and in our case as well donations) helps pay the bills. However, there is a limit to what can be consider acceptable. Small non-intrusive text (or even image based) ads are good. Pop-ups, pop-unders and Flash based ads are what can be consider intrusive.
Starting with Adblock Plus (ABP) 2.0 for Firefox and Chrome, ‘non-intrusive ads’ will be shown by default. This can be turned off via the ABP preferences and if your are using a ‘privacy’ filter, those ads likely won’t be visible anyway.ABP developer Wladimir Palant explains
Starting with Adblock Plus 2.0 you can allow some of the advertising that is considered not annoying. By doing this you support websites that rely on advertising but choose to do it in a non-intrusive way. And you give these websites an advantage over their competition which encourages other websites to use non-intrusive advertising as well. In the long term the web will become a better place for everybody, not only Adblock Plus users. Without this feature we run the danger that increasing Adblock Plus usage will make small websites unsustainable.