i personally like php... but i work with a lot of commercial enterprise class solutions and a vast majority is based on asp...
I use PHP. In the beginning because it was easy to get help from the many forums, tutorials etc. As time have passed, I have grown to like it very much. I don't think I've had a problem yet. Where I could not find the answer or a partial answer by doing a quick search on G or a forum.
I have been fortunate enough to use both PHP and ASP.Net in commercial settings (getting paid for coding) and both have their pros and cons. However, if I were to concentrate on one, and was hoping to make it part of my career, I would choose the Microsoft path. I have been in the IT for years and see there is more demand and higher salaries for .Net programmers. The last place I worked for was a survey company for HR departments across the US and I had access to accurate data for the web programming area, and the Microsoft related jobs always paid higher than the PHP jobs.