Compiled the following earlier based on tests done at
www.imaging-resource.com They haven't done the measurements yet for D80 and 400D though. The second table is more relevant for AF speed comparisons (lenses cause a big difference).
camera (prefocus lag/manual lag)
Nikon D50 (113ms/134ms)
Nikon D70 (124ms/155-168ms)
Nikon D2H (45ms/46ms)
Nikon D100 (100ms/100ms)
Nikon D200 (57ms/57ms)
Nikon D2X (44ms/44ms)
Canon 10D (104ms/146ms)
Canon 20D (77ms/110ms)
Canon 5D (78ms/133ms)
Canon 1D (39ms/54ms)
Canon 1D Mk II (54ms/75ms)
Canon 1DS (59ms/83ms)
Canon 300D (142ms/248ms)
Canon 350D (95ms/168ms)
Fujifilm S2 Pro (162ms/220ms)
Olympus E1 (76.5ms/173ms)
Olympus E-300 (100ms/370ms)
Olympus E-500 (95ms/320ms)
Pentax *ist-D (130ms/180ms)
Sigma SD10 (111ms/no timing for manual focus)
Kodak DCS Pro 14n (119ms/128ms)
Minolta D7D (117ms/253ms)
camera (autofocus lag) lens
Nikon D50 (265ms) AF-S 18-55
Nikon D70 (342/486ms) AF-S 18-70
Nikon D100 (150ms) 24-85
Nikon D200 (210ms) AF-S 18-70
Nikon D2X (44ms) ?
Canon 300D (250/278ms) EF-S 18-55
Canon 20D (160/150ms) EF-S 18-55 USM
Canon 5D (149ms) 100mm macro
Canon 350D (240ms/220ms) EF-S 18-55
Canon 1D Mk II (200ms/240ms) 16-35 F2.8L
Canon 1DS (93ms) 100mm macro
Olympus E-300 (360/370ms) Kit 14-45
Olympus E-500 (370ms/380ms) ?
Minolta D7D (266ms) ?