For web development , dotNet is the best.....
Java is heavily used throughout the industry. It is now open source so does not depend on Sun alone anymore.
Advantage of Java is that it can run anywhere while Microsoft stuff only runs on MS systems.

Well to clarify a bit, both of those languages have the capability of being used as web development languages but neither were made specifically for that purpose. .NET itself is a framework, ASP.NET is the web language in the framework.

The problem lies in the fact that you already know .NET stuff and will have to go through the learning curve of Java. But Java can do anything you did with .
The expense of moving to Java is only in time and any money spent would be minuscule to what you pay for MS licenses.

Disagree, JAVA FOR THE WIN ! ! !
It was always open source as that was the idea for whole time unlike Microsoft products that are still very expensive even thou they provide you these days with some "express" editions
Larger community support, plenty of things for free , I like security of Java and I also see Java sites running faster as most of .NET website which are poorly programmed.

yaa...
Java is java..
i agree with you...

Since you are familiar with Java, I suggest you should go with Java. Different people prefers different languages.

I agree with others saying that Java is widely used. Since it's free and no license required, there is no additional cost for it. I would go for Java and use the licenses' costs for other purposes.

Anuj,
You're right, .Net is used more for web applications development as compared to Java which is used for enterprise server based application development. Moreover if you're not already experienced in Java for at least 3 years, it is now difficult to get a Java job (talking about India). On the other hand you have a much better chance to land a .Net job as a newcomer. So I would suggest you don't look left or right and go straight for .Net

hey Daivik,
Thnx for the reply. What do you mean by saying that if i dont have 3 yrs experience in java i wont be able to get a job easily.
Does DotNet have more market value than Java ???
What I've heard is that java is in more demand and also it is less frustrating than DotNet.
Please clear me in this coz m currently in 3rd year doing Computer Engineering and i want to have a clear vision of this topic(Java or DotNet).

hey dude u must go with java...
it is best language than the other (i.e .net). and bcause of simplicity and already frames of .net most of the people r goes with .net so there was large compition of jobs..
java r portable language and most of the industry are usig it for developing softwares thatswhy oportunities of jobs automatically increases....
so go with java.
-PRAMOD.