Well Ken, I have recently switched from a Dell Latitude to the Powerbook G4. The Powerbook I purchased is of the exact configuration as the one you're considering and have been using it for a little over a month. The only thing I can tell you is that I should have switched sooner.
The quality as compared to Dell is amazing, I love not having to boot my computer every time I need to work on it (you shut the lid for sleep and it awakens in about a second when the lid is opened), the user interface is clean and intuitive, and what I love most is the ability to just work without the computer and the OS getting in the way.
As for your questions, you should be able to get the student discount when buying from retail stores. Just remember to take your student ID with you.
Ken.