Oracle Database Discussions

Sorry to post this here, but I need so insight and don't know any Oracle DBA's. As posted here before, Ive been a MSSQL DBA for about 6 years and want to broaden my skill set. One of my ideas is to learn Oracle. For the record, I do realize that my teaching myself wont open up hundreds or Oracle DBA jobs, but Im hoping to land a "mostly SQL with a little Oracle" gig somewhere. Ive successfully installed Oracle on Linux, and now need to make a decision on if to proceed or not. Any insights from people that have worked with both platforms would be especially helpful, but all thoughts are definately welcomed. So now my questions:

1. Why are Oracle DBA's paid more than SQL DBA's? It must be something skill specific? What is it?

2. Will this trend likely continue as newer versions of Oracle are released that are easier to manage?

3. With that extra cash, is there typically more hours involved? I dont mind working a bit extra if needed, but I do have little ones that I'd like to watch grow up.

4. Are there typically differences in the job responsibilities between Oracle and SQL DBA's? The changing trend these days is to include DTS/ Analysis Services/ Reporting Services all under the DBA umbrella. Do Oracle DBA's typically have the same type of stuff?

5. If I do continue down this path, it would probably be far easier for me to learn on Windows than *nix. Is this a valid thing to do, or should I not bother? I've been told that it's still worth while, but have real reservations about needing to tell an interviewer "I've only used it on Windows".

I realize this is all subject to personal experiences and feelings, but don't know how else to figure this stuff out without asking.

TIA, ChrisR