I'm not quite sure what you're trying to imply here. I bet there are substantially more people using outlook today than IBM PCs in the early 80s, or web users i

I'm not quite sure what you're trying to imply here. I bet there are substantially more people using outlook today than IBM PCs in the early 80s, or web users in 1998. There are viable alternatives to outlook of course, but I suspect it'll be around for some time. At the time the IBM PC was released there were also plenty of viable alternatives, and I suspect it wasn't so obvious which one would win at the time.