I think outlook integration is a great idea. It's free with outlook express. For those that don't want to use it, it shouldn't get loaded and then it won't take up any more resources and it saves you from having to rewrite a ton of parsing code for csv files etc. Who cares about prioritization, it takes all of 15 minutes to write the code to open up outlook and read an address from it. It's better to design it in early on then have to rewrite everything later.