Hi Alan and all,
I cast my vote for Adwords as well, we have used them on numerous occasions, and with a little keyword tracking and focus, we have seen constant and profitable CR%.
HOWEVER, my last campaign brought in an attrocious CR% (1/10th of a percent... arghhh!) no matter what I did - and I KNOW that my page is selling with supposedly similar traffic, with Google organic search (with many, many different keywords being used), THE SAME EXACT PAGE is bringing in 8% - that's 80 TIMES BETTER!! This is with a sample of well over 1000 visitors. I'm not exaggerating. My partners and I have a lot of experience in these matters and we admit to being baffled in this case... I simply dropped Adwords.
Please don't ask me about Overture or Espotting, I don't feel like swearing this early in the morning...
Have a good week,
Tim