<p>I am not really familiar with Maven program but I've been using Eclipse for quite a while for Unit testing, code coverage, javadoc generation, code style checking, etc. Probably, the only main thing that I didn't really like about Eclipse is the "compilation errors" that it generates when you are running Eclipse and Ant simultaneously. So I am wondering if Maven 2 does the same thing if you are running Ant task.</p>

<p>Lee23 </p>

The company I currently work for has a lot of JUnit tests which are run using Maven (1.x). We've never really had any problem and any tests that fail in maven can be debugged using the remote debugger or in Eclipse on their own.
The most important thing is that you take the time and effort to set up the environment properly so that when your tests run they are using the correct directories, variables, etc. This way you shouldn't get the 'compilation errors' that you would get when running Eclipse and Ant.
Maven has the ability to run all your tests for you during the testing cycle of compilation, this should stop the need for any Ant tasks to run the tests. However, if you still need to have scripts for other tasks (generation of code, etc) then be weary of Maven's ability to generate code and not include it in the compiled binaries (jar, war), though this may well be fixed for newer versions of Maven.
At the end of the day it would be best to evaluate Maven 2 and see if it's right for you. It sounds like you're having (sarcasm)a lot of fun (/sarcasm) with Ant and Eclipse already though. :)