I agree with what everyone says...that being that lighting is the most important part of watch photography. As a working photographer I have several high end digital SLRs and a huge lighting system but for most of my personal watch pictures I use a little Canon S-95 point and shoot and window light. I use a couple of pieces of white foam core to reflect light, fill in some shadows and create some highlights. The biggest issue when shooting highly reflective objects is controlling the highlights and shadows and reflections.

Whatever type of camera you get, make sure you have a macro mode and that you can turn off the on-board flash. Before you buy a big lighting system use window light (not with the sun coming directly in) and a couple of reflectors for a while.

JohnCote