Sony is in the Business to sell not only Readers, but more importantly to sell content. You mentioned in your first post the iPod/iTunes model. You have the analogy correct, that is what Sony hopes to achieve with Reader/Connect.
When iTunes started the collection was small. You could play MP3s on your iPod (like RTF & PDF on the Reader), but for DRM, only iTunes content will play on the iPod. Lots of folks complained. Many still refuse to use an iPod for that reason. Still the market supports the Apple model. Clearly Sony is trying to copy it in books.
One size does not fit all. Good Luck