This is just a marketing stunt by Nvidia, and should be taken as that. Of course their conclusions are optimistic, it's the typical marketing BS. As a PC gamer I'd like it to be true though.
However it should be noted that the data comes from DFC (as is specified in the charts), which is a market research and consulting firm centered on the gaming bussiness since 1993 (I googled DFC to see what it is). Nvidia is just basing these charts in DFC's forecasts released recently, just like I supose many other companies whose bussines is centered around gaming are doing at least to a degree, I guess they use many sources.
http://www.dfcint.com/wp/?p=311
http://www.dfcint.com/wp/?p=48
My point is that Nvidia is not "smoking anything" or doing anything like that as it has been suggested more than once, they are just using which is (probably) the most optimistic forecast out there, because it benefits them. But the forecast is legit and is out there for anyone to use. I think it is important to be accurate on this, a market research firm has published these results, it's not wishful thinking on Nvidia's part. Whether DFC is smoking anything or not, that's a different thing, but I guess that if they are in the bussiness since 1993 it means they do their work as well as any other market research firm.
EDIT: I'd like to also point out that the decrease on concole games makes a lot of sense to me. Next-gen consoles are expected sometime around 2014 or 2015 last time I heard. So I expect far lower console games sales from 1 year prior to the release to 1 year after the release. The reasons are
1- No more Xbox360/PS3 consoles sold in anticipation of the new gen, which means no growth in that market. In part is this influx of new consoles which drives a large proportion of games sales. People with new consoles need to build up a portfolio of games. People with a good portfolio tend to buy a lot less.
2- People will save up for a new console, so that will prevent them from buying games other than the most anticipated ones.
That was true when Xbox360 and PS3 were released* and it will be true again in the future, and that's without accounting for the fact that PC gaming is becoming much stronger (awareness, digital distribution, stronger IGP/basic GPU) and that mobile devices such as phones or tablets may steal a large part of casual gamers off consoles.
* And even then sales were probably better than they could have been if both consoles had been released at the same time, since PS2 games still sold a lot more than XB360 or PS3 games most probably will in the coming years, because the past generation sold a lot more consoles than this one, specifically the PS2.
