We’ll I can tell you that I’ve experience similare speed-increases as Walter, if not more. I don’t have all the figures in front of me but here are a few:
20s Uncompressed 10-bit 4:2:2 HD to MPEG2 HD (1-PASS VBR + AIFF Audio)
Dual Core 2.3 G5: 68s
Quad Core 2.5 G5: 42s
3x20s Uncompressed 10-bit 4:2:2 SD to MPEG2 SD (1-PASS VBR + AC3 Audio)
Dual CPU 500Mhz G4: 300s
Dual CPU 2.5 G5: 70s
Quad Core 2.5 G5: 37s
That’s what I call a GOOD speed-up!
In After Effects I’ve gone from little over five hours to below two hours in rendering speed (Dual Core 2.3 vs Quad 2.5). With-out the NUCLEO plugin I was at about 7 hours on the same sequence