One of the features that I really like about Leopard is iChat’s ability to do Screen Sharing. There have been different implementations of screen sharing including Apple Remote Desktop and VNC, but none is as easy to use through home routers as this. In the last week, I helped my dad with email (he just upgraded to Leopard) and helped a ReceiptWallet user with an issue. Sometimes it is much faster and easier for me to poke around than to talk on the phone or exchange email. While there are some problems with the feature dealing with different screen resolutions, for most people it works quite well. This feature, alone, is a reason to get anyone that you support to upgrade to Leopard; if you’ve ever spent hours on the phone trying to talk someone through a problem, then this is for you!
(Of course, certain firewalls and routers can cause this to fail. I got rid of my Linux server awhile ago that was my router and now things like Screen Sharing work quite seamlessly. If you have problems, stop kidding yourself and buy an Apple TimeCapsule or Airport Extreme and be much happier. It costs more than other routers, but the time and hassle it saves is well worth it.)