I have recently been involved in a large amount of web design research for an international client, and made some keen observations about how bad advertising can ruin sites with good design principles.
Let's take a look at the very popular faith site called beliefnet (1 million plus views per day) and look at a page on the site with advertising. Beliefnet was not chosen for any other reason than it's the first one that came to mind when I thought of bad advertising on a site with some good design.
Now let's look at the same page with no advertising:
A little easier on the eyes isn't it? A nice sense of white space and vertical continuity. Although I think the adverts for "finding your ancestors" were rather tasteful, I could say much less for the "psychic readings". Just look at those two ads for a minute. One has a fair degree of white space, the other has much less. Not only is white space playing an important part in the advertisement, but colour is also. I find the ancestors ad to be far less obtrusive, my eye glides over the text and finds balance in the advertisement. The palette in the text compliments the canvas coloured background, and the colour also complements the site well. The mixture of script typography with serif and sans-serif fonts tells me that they have some sense of style. It seems classy.
The psychic ad is much more obtrusive (and actually glows on the page). The white space balance is relatively non-existent, and its massive sans-serif type overwhelms the page. It especially overwhelms the menu, which then begins to feel a little bit condensed. When I first visited this page the content was immediately distracted by the glowing live psychic ad. You could say that this is "good advertising" in that it draws your eye directly to the ad, but the problem is that it doesn't draw your eye in a positive manner. Immediately I recognize it as an ad, and think to myself, "That's an ugly ad. It's really distracting". The odds I will click that ad become less than 0— especially since it degrades the rest of the page content. So, although it did capture my eye, it didn't cause me to click and now I'm wanting to leave the page altogether because it is so distracting. This to me defines bad advertising.
Take a look at the same page without that ad:
Though the page definitely feels cluttered, the menu on the left pops a little more and you as a reader feel less sandwiched by advertising. Now, let's assume that they have that advertising there because they need to generate revenue and really can't afford the white space even though they know they need it. So what do we do? Well take a look at this next concept.
and one more...
Notice the difference here. The colour scheme of the ad matches that of the site in a complimentary way. Perhaps the text isn't perfect, but bear in mind this example was done to illustrate a point. Take a look at the new version compared with the old version below:
Notice how the new version on the left is much easier on the eyes. You feel as though you may be able to stomach reading on the page, and somehow the gentle blues are a little more soothing to the eye than the obtrusive flashing purple.
I think the "Wholeness" ad on the page could probably use some retouching too, and in general this site desperately needs white space, which becomes apparent when you look at the page with no advertising. Beliefnet does have a good site, but in this case the design is being clouded by obtrusive ads.
If you are thinking about advertising on your site, make sure that the adverts are complimentary to your design—or you too may run the risk of having your readers turned off by distracting advertising. Nobody likes reading advertisements, but if you do have to have them, make them subtle, and well integrated thematically with the overall design of your site.