Different Ads. for Different Browsers?

I see two different things.

[asas111]

I discovered this by chance. When using Netscape, I see different ads. from the ones I see under Internet Explorer. I tested this many times, different times of the day, and I keep getting different Ads. for both. Almost never the same.

I use IE 99% of the time, but lately I have been doing some testing with Netscape when I discovered this.

Has anyone see this and how can you explain it?

[jomaxx]

Two possibilities I can think of offhand...

- Different cookies (telling Google something about you, e.g. your search/browsing history).

- Different language settings; even something like "en" vs. "en-uk" might make a difference.

[iwannano1]

Also Google may be targeting ads towered diffrent browser

[moTi]

i'd suspect firefox users for example have very different demographics than explorer users. younger, more techie, maybe educational background, surfing habits..

it would be unreasonable for google waive these income optimization opportunities and not to factor this into the ad distribution algo.

[koan]

I just noticed this on a new site (few months old), after posting a new article on Firefox (my default browser, of course), the ads were completely unrelated, but when I tested my article on IE 7.0, I noticed the ads were right on the spot. I checked again and they were still completely different in Firefox (like one being about trains and the other about vegetables). I think it resolves itself after a few hours but it is still a strange behavior, which might give us clues on what Google uses to target users.