Some new plugins have been made available...

Nokia themselves has provided some new plugins for previously unsupported phones:

Nokia E50

Nokia E60

Nokia E61

Nokia E61i

Nokia E65

Nokia E70

Nokia N76

Nokia N93i

Nokia N95

Nokia 6290

You can find them on the Nokia website here, along with some good directions on setting up your Nokia phone to work with your Mac, here.

Additionally, Julian over at Mobile.Feisar.com has updated his list of supported Sony Ericsson iSync plugins, now with USB support:

K320

W710

K510

W850

K550

W880

K618

Z610

K810

Z550

W300

Z710

W610

Z558

W700

V630

W200 (USB Only)

You can find them here.