Bob's seen the writing on the wall
GoDaddy may have market share, however the market has shrunk considerably, almost all holders of what seemed like good names have reduced their portfolios, so the domain name business is a shrinking business, not an expanding one
Bottom line is, that in almost all cases, you need to build a website with traffic, real value and a real money making business or the name is worthless
Yes, there may be a blip in increased business with all the new TLDs, but that's all hype and those TLDs will all fail ( watch what happens to .xxx in 2 years and look into the value of having a .biz domain now )
It's likely the hype behind these new TLDs that is pushing the price up beyond the $1 billion that's been floated months ago, and I'm sure there is still profit in GoDaddy, but it is at best a level business in these poor economic times with little hope for growth.
Bob's a smart guy, getting out and moving on, while the getting is ok .. if he had been a genius though, he would have gotten out by 2004 and probably gotten $10 billion for the business