The SE traffic is definitely starting to go downhill quickly, that is one of the reasons I have started to work on LL and TGP traffic in the last few months. Our SE stuff still brings in the revenue, but the TGP traffic is starting to look promising, especially since bandwidth is dirt fucking cheap
I really think the one's that are going to be making the money long term are those that craft pages that are tuned for conversion. I see so many people out there just throwing bandwidth at a page, and not really understanding why a person clicks or doesn't click. There is a science to it, and unfortunately just like getting listed in the SE it changes from week to week
Tim