The sad part is that we really did get a lot of it built. In fact, by the time Apple finally shipped Safari with proper tabs we were readying a private beta.
This is the problem with trying to write someone that Apple is working on. The bult-in solution will always be more popular, and the in-house developers almost always can do the same features better. So any attempt to beat that has to be very good or offer completely unique things. Sperte and his team thought that is what they were doing, but it’s hard.
(via Shawn Blanc)