Hi! I am a long time lurker that has finally decided to join you guys. Let me start off by saying that this website is amazing. I have learned a lot by browsing the threads. I currently only own a Sony DSC W7, but I am going to make the plunge and purchase a Canon Rebel XTi within a month or two. I am really new when it comes to SLRs and would greatly appreciate any pointers that you guys could give me. I am really in the dark when it comes to lens purchasing. I enjoy nature and would love to shoot wildlife photos, but I am unsure of what mm lens to buy, and is the IS really necessary if I am shooting from a tripod? Also, what kind of range could I expect to get with say a 70-200mm lens or the 100-300mm lens? Any information/help would be greatly appreciated. Thanks in advance.