Check past financial statements from ATi and NV where the companies show the breakdowns of revenue by market segment.
In home consoles at least, due to the way the licensing worked, the design was licensed to the console manufacturers and then ATI/NV got a cut from each console sale, as well as (I believe) payments for the use of the IP.
Based on my maths using the 2008 AMD financial report, console revenue was a little over 1/12th the revenue of GPUs (,~$91m to ~$1050m) and that was when 24 million Wiis were shipped, and some amount of Xbox 360's that I do not know because I can't be bothered to look it up.
If you think the PSP sold on average 12m units a year, and in the year the Wii sold 24m and the Xbox sold some, GPU revenue outstripped console revenue for ATI by a very large margin, do you think that Tegra will be that big just from one design win for NV, especially when they have far more profitable areas of business such as Tesla and workstation cards?
I'm not saying it's bad, or that it won't make money, just that it's not going to be "huge" unless the entire world buys a PSP2.