I, too, believed that this would be the easiest way to go. When I wanted to transfer my brother's e-mail to his new Powebook half a year ago, though, this method did not work for me. There were problems with the line endings, all the messages in a mailbox stored in on the Windows machince showed up as one single big message, garbled together. Obviously, it was not seeing the end/beginning of the individual messages. I assumme this has something to do with the different line endings on Windows/Mac.

Anyway, I ended up transferring all mails via an IMAP server. I can really recommend this method, it is straightforward, easy, intuitive - drag & drop, actually. It's a big advantage if you have access to an IMAP server with more than just a handful of megabytes quota, else you have to do your transfer in many chunks so you don't exceed your quota.

Although I did have access to such a server, I set up a local IMAP server on the Powerbook directly instead. The reason was that I was at a location with a slow internet connection and this way I did not have to first upload and then download hundreds of MB, I could alll do it locally between the two computers.

I used the IMAP server from the UNiversity of Washington. There is a hint on this site (too lazy to look it up now) which links you to a page with detailed instructions. There are some tricky parts in there, however, e.g. regarding server certificates, so some experience with Terminal & Co. is needed.

Conclusion:
- If you don't want to install anything and have little experience, check if you have access to an IMAP account - e.g. from a friend etc.
- Set up a local IMAP server if you are an experienced user.
- Else the mehod described can work for you, especially if you are beginner. Depending on the number of messages you would like to transfer, this can quickly become very tedious however.