A CPU's maximum theoretical  floating point performance as you have listed there... Actually has very little to do with how powerfull a CPU really is. - Especially so as CPUs generally aren't simple dumb floating point processors, they can do some very heavy branchy integer stuff too, which is just as important.

Besides, it's IBM's marketing pitch, Sony and Micrososft have a vested financial incentive to grab those numbers and run with it for advertising to suck people in.
The very narrow 2-issue in-order cores both consoles use also happens to be very deeply pipelined, with a poor branch tree predictor on top of it, it's slow. Painfully so.

I'm surprised how often people throw those numbers out on this website without actually understanding what it is and why they simply aren't accurate.
There is no doubt the PS3 is more powerfull than the Xbox 360 in terms of theoretical performance... Anyone who argues that is silly, but those numbers for both consoles are simply false.

take a chill pill. PS4 will be the best video game console of all time like every other PS consoles ;) Sheesh.

Okay here's the comparison. The world's leading authority on computer science here (self-proclaimed).

The Xbox 360 can potentially do free z-buffer and frame-buffer operations - but due to exceptionally low main memory bandwidth - that doesn't help too much. That's what we really need. It's limited by the main memory bandwidth. The main bottleneck:
25,600,000,000 bytes per second / 60 frames per second = 426 Megabytes/frame

How many vertices can that support? 32 bytes per vertex, gives:
426,000,000 bytes / 32 bytes = 13.3 million vertices per frame

However - the rasterization requirements vary tremendously. Let's assume 5 z-compares per vertex, 5 pixels, that'll raise the bandwidth requirements to:
13.3 million vertices per frame * 60 = 798 million vertices/second
798 million vertices/second * 5 * 8 bytes (z-read, z-write) = 31.920 GB/s of z-buffer bandwidth

It has the on-board z-buffer. However, in actuality, it needs half that memory bandwidth for textures. Thus it only needs half of that for z-buffer bandwidth. 16 GB/s of z-buffer bandwidth. How much memory bandwidth does it need for the textures? Let's say the scene is at 1280 x 720, with 2x AA, 32-bit textures, 4:1 texture compression (actually 8 bit textures), and trillinear filtering:

1280 * 720 * 1 byte * 60 frames per second * 8 samples (trillinear) = 442 MB/s

But let's say we wanted to do more advanced forms of texturing:
1920 x 1080 * 4 bytes (no compression) * 60 frames per second * 16 samples (anistropic filtering) * 4 samples (4x anti-aliasing) = 31.8 GB/s

It only has 25.6 GB/s. Thus - it has a disadvantage in the texturing and resolution department to Playstation 3, although it has an advantage in raw vertex pushing. Because Playstation 3 has a CPU which can do vertex pushing, and it can dedicate its GPU just for rasterization (with all 25.6 GB/s available for that), while Xbox 360 can't, Just about equal therefore. It could really use an on-board texture cache as well - then it would not have that disadvantage in texturing/resolution. Gamecube uses a texture cache.

So their GPUs are just about equal, in fact, they have similar transistor counts, but in the CPU department, with 25.6 GB/s of dedicated memory bandwidth, and 7, 128-bit SIMD mulitply-adders, the Playstation 3 is light-years ahead.

Thus the winner in terms of overall performance is of course Playstation 3. Although it takes a little effort to use it all.