This conversation is making the rounds again…

http://stephendeken.net/index.cgi/2006/11/15/Vector_Vs_Raster_The_Fools_Game 

Most of the conversation isnt working WPF into the picture. Using things like DrawingImage really changes the whole game.

What I think it all boils down to is use the right tool for the right job.  If you are only doing a 16×16 icon and targeting only fixed resolution devices… then vectors might be more expensive than necessary. If you are targeting multi resolution devices vectors can be very beneficial. Creating iconography with mixed media (vectors/rasters together) is where its at though… DrawingImage supports this nicely. One thing that I think is really hot is embedding DrawingImages in DrawingImages… I tried it out the other day and it worked great. You can have reusable elements in your icons being shared across icons.