[NinjaWarrior]

> Both Unity and Unreal have their engines running well

Running well? You'll know there are still tough problems next year. No one download 100 MB or 200 MB scripts and assets to play a game. In the past, all such resource rich Flash or Unity Web Player games have failed. No exception.

The relief is Mozilla people actually know this problem (I talked with them at GDC).

AAA games are just too rich to "browse" on the web. People close their browser windows within several seconds. Typical home internet bandwidth is narrower than Blu-ray or DVD-ROM, even in advanced countries. Furthermore, browser cache can't handle big resources. You won't even gain server costs.

[rybosome]

Have you played a flash game lately? The initial program begins running really quickly, where it then downloads assets using a separate loader while a splash screen displays. Sony also ran into this problem with the massive files (20 - 40 GB) for their disc-based games that are also available for download, but somehow (in many cases) the games can be played while the download is happening, as the most critical parts are downloaded first.

Browser gaming may or may not take off, but I really don't see asset-size being the rope with which it hangs itself.