I hate to say this, but don't listen to these people. There are major differences. Performance is definitely improved for Windows servers, but that is really the least of the changes.
1. Input/output filters: this alone is a major advance over every other webserver out there. It allows for output from module A, such as PHP, to then be filtered through Module B, such as mod_perl, and then for THAT output to be filtered through Module C, such as SSI. Each of these modules can essentially treat the output of the previous module as if it were a file to be parsed. The implications of this have not even begun to be explored.
2. Ability to run in several different modes, such as threaded, process-based, hybrid (processes+threads). This greatly affects possibilities for scaleability, which is not the same thing as performance.
3. Streamlined configuration system (yes, it won't necessarily just "work" with your old httpd.conf. You will have to learn some new things. Get used to it.) Webmin is a nice tool, but it's not ready for Apache 2, and serious sysadmins shouldn't need Webmin anyway.
4. Multi-protocol support. It's not just a webserver, and it's not just limited to serving HTTP. Again, possibilities not really explored by many people yet.
Etc... See the whole list of major changes at
Should you upgrade? Not if you don't want to learn anything new, and if evenything you have is working just fine for your needs. But, if you want to be ready for the future of serious webserving, you should pick up Apache 2.x sometime. Also, in my experience, performance on Win2K is an order of magnitude greater than Apache 1.3. In fact, Apache 2 brings all the speed of IIS to Win2K with none of the security problems ;-). -------------------------------------------
"Now, this might cause some discomfort..."
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