The new logo is much wider than the previous one and on the top right corner you can see something that looks like chip. Core i7 and Core 2 Extreme logos are black, while Core 2 Quad, Core 2 Duo, Core 2 vPro are blue and very similar.
Many Centrino logos are all in white, and the top one is Centrino 2 inside, runner up is Centrino 2 vPro followed by Centrino inside and Centrino vPro inside.
Itanium, Xeon, and Core 2 Viiv sort of didn't change their format, while Xeon will come in new blue colour, probably for Nehalem based Xeons. New logos will be effective as of April 1st, the first day of Q2 2009.