Although I have some experience on Java programming, I'm a newcomer on Visual J# 2005. Does anybody know this plataform and can sincerely tell me how good it is?

If you want to use the Java language and the .NET Framework then J# is the way to do it. I think that C# or Visual Basic are both better languages but that is largely personal opinion. And I work for Microsoft so you would expect me to say that. :-)

J# does not include all the latest features of Java 5 though so it is somewhat limited that way.

I guess J# is a tool used to attract Java programmer to .NET

in my opinion, J# is not good, if you like Java language, recommend use sun Java