You can't export the timelines to another project. But, as I say in my books, by using Share/Personal Computer/AVI, you can export the rendered file for use in another DV project.
There is also a third-party program called ClipMate that will allow you to copy sequences and paste them into another project, and some people have found success using it.
But the "official" way is to export an AVI of your finished sequence to mix down in a master project with other AVI sequences.
OK Thanks Steve,
I'll do it on the rendering way and make AVI's.
One thing to consider is that all edits from Project A will now be written to that Exported/Shared DV-AVI. One can either edit completely and finally in Project A, so that everything appears in the DV-AVI as it does in Project A, The other method is to edit very loosely in Project A, leaving plenty of Handles in each Clip in Project A, and no Transitions (will be added by doing Cuts to the the DV-AVI in Project B), and then doing the tight edit in Project B. Only you can determine which method works best for you. If Project A is perfect, then just Export/Share that to DV-AVI for Import into Project B. If you are not sure that you have everything perfect in Project A, then just do a loose edit.