I asked Colin about tours and traffic ratios ( guess he didnt know ).
With each tour page you see a decrease in clicks.
Example:
Tour Page 1. 100,000 hits
Tour Page 2. 80,000 hits
Tour Page 3. 40,000 hits
Signup Page. 5,000 hits
I have always been curious as to what the acceptable dropoff is between each page. Nobody has ever been able to answer me but then again I may be one of the few webmasters who actually looks at these things.
Also, gothweb .. you said you wonder if its worth the time to make the 'enter' link larger when it only offers a potential 25% increase. Lets say the increase is only 5% .. would you accept a 5% increase in sales if it was offered to you ?

Im just thinking out loud .. And besides, if 80% of your traffic hits the homepage then enters the next page I thinks thats a damn good ratio. I dont have anything to compare with except my own numbers but thats right on target.