ATI are about to become the leader? They are already the leader in all categories: perf/$, perf/W, absolute perf, and at all price points. See list below. For gaming performance, the GFLOPS rating are a roughly (+/- 30%) good enough approximation to compare ATI vs. Nvidia. For GPGPU performance, the GFLOPS rating is actually unfair to ATI because Nvidia's GT200 microarchitecture causes it to be artificially inflated (they assume a MUL+MAD pair executing 3 floating-point op per cycle, whereas ATI assumes a regular fused MAD executing 2 floatting-point ops per cycle). Meaning that an ATI GPU rated 200 GFLOPS actually executes ALU-bound workloads as fast as an Nvidia GPU rated 300 GFLOPS. ATI's lead is such that it's not even funny anymore. There are rumors of Nvidia killing the high-end (GTX 285, 295) to focus only on the extreme entry-level segment (sub-$100). And GT300 (Fermi) will not enter mass production before the end of Q1 2010. I am concerned by the lack of competition... ATI is free to impose whatever price structure they want.
Anyone can make an omelet with eggs. The trick is to make one with none.