Loading Unity3d web player as a separate Pop-up window

Can someone elaborate on why (big) games like Fusion Fall (by Cartoon network), Tiger Woods PGA Tour (by EA) load their Unity game in separate browser window instead of the same window or a new tab? Is it because of the performance or any other problem like Unity plugin crashing etc. If you were to run a website based mainly on Unity, what is the best way to display it? Will it be better off being run as a part of the website like these Flash banners/websites or will it be better to have a separate window popping out of your website to display Unity Content.

Even though it is not related to Unity, this is regarding the plugin behavior in different browsers. Do different browsers allocate different memory (processing/cache) for Unity? Fusion Fall for example has a separate version for FF and other browsers.

I just created this topic in the forum because I couldn’t find any suitable answer over here:
UnityAnswer page

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