...the stuff that follows is my opinion [lol]:
TFC = complex, fast, intelligent. TF2 = simple, slow, pretty. FF = complex, fast, intelligent, buggy/bit unbalanced. NS = Complex, fast, intelligent, strategic, original. NS2 = ?.
Regardless of playing styles and preferences, marketing principles stay the same. During peak time, FF had only 1,600 people simultaneously playing it (over 100,000 DL's of it over 4-5-6 days, www.fortress-forever.com). TF2 had like 5,000 people playing it simultaneously after only a few hours. Having TF2 bundled into the orange box helped a lot, but still--the market is out there for superior source mods. My point was to advertise through multiple channels, as a lot of gamers don't buy a product unless it's A) talked about everywhere B) a sequel or C) they're already very familiar with the product or company.
NS:S will not be a hit, but NS2 will be b/c of the (hopefully) new gameplay, maps and players. Just gotta make sure that those millions of CS and WoW players realize that NS2 is coming and that it will be huge! If people don't think something is going to be successful or good, then it won't be. Gotta make some uber videos (im sure some of the beta testers will help you out on that one or some of the long time fans will), get interviewed from various (lots and lots) sites (even perhaps some large CS and WoW sites) -and magazines-, and enable pre-orders

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