I added bug 1966, ctrl+enter doesn't move the cursor to the next line immediately. You have to type more text before that happens.
While this doesn't actually prevent one from breaking lines (in addresses and such), it confuses beginners so much that it is a useability problem. And a regression too, I believe lyx 1.3 did this right. I can also imagine reviewers getting hung up on this. Helge Hafting