LAMP is the McJob of Web Development
L - Low paid
A - Adolescent/Amateur
M - Male
P - Programmer
Sorry, I do love LAMP, but Java and .NET programming jobs pay 50% more on average. They're also 1000% more available. I'll be impressed when I see a resume/CV come across my desk for an exclusive LAMP developer that's not a 19 year old trying to bypass college and hop into programming with a long list of personal sites for a portfolio. Until then, LAMP is just what kids and young adults use at home for their hobbies because it's free and so fits with their part time jobs or allowance.
There are exceptions to every rule, but when I see mid-level LAMP developers pulling down $80K+/year (on average) I'll be convinced. Right now they're just $40K/year linux fanboys copy and pasting code from help sites.