With lots of contents and game info, how do they manage all the data? Do they hard-coded the script themselves? Any script I can find that nearly capable to do something like this?
They usually use a ready system/cms and as time goes by they modify it heavily,at the point it isn't the system they used to use.
They probably used a standard video arcade/content management suite and modified it for extra features. A team of 4 could build one of these in a month, if they have a company code library like mine has. We code in our spare time, just random crap, that becomes useful and time saving later on when a use comes up for such code.
Wow.. phpl33t, your team can develop site like this in month? Care to share how much you guys charge for site like this?
There are low cost gaming CMS-es available that might offer what you are after - Game CMS and Cigmas are two I can think of off the top of my head. They aren't as 'industrial strength' as the big sites, but they aren't bad, and they're cheap.
Gamespot is owned by CNET.com and is by far the biggest and most successful gaming website - so i'd assume its a purely custom job. That said, as mentioned, there are plenty of content management systems that can do the basics of what Gamespot does - personally i'd recommend CustomCMS