It definitely is not a waste of time.

I started on PHP years ago have picked up Javascript then LUA and have tampered with C and assembly. PHP is were I got my start and as it is 100% free to learn it (which beats most other languages that need to be compiled). And that will allow you to use it as a big stepping stone into many other languages.

dschreck's post is on the money. Having worked with linux it gives you some options you may not have with a windows server. And I am confident PHP can go head to head with ASP. After all that is what they designed it for.

But the point on how many of us will ever build a site that serves millions is a good one. I have done a site that came close to the 10K mark and that was an intense project not sure I would even want to be involved on anything much bigger (too many cooks in the kitchen).

Now to the issue of frameworks. I must admit I have never used one. Of course every name mentioned so far I have downloaded tried for various things and basically at the end of the day I always found I need something custom made and hated having to modify someone elses code. So I usually build every thing from scratch. Well if you don't count the copying and pasting from some other past project.

If you use a framework makes sure it has all you need or there is mod for it to get you what you need because if you have to change even the slightest thing it could take days just to track down were the exact lines of code are you need to change.