Not trivially, no. You may want to check out this post on version control workflow. You will probably need to end up writing your own serialization/deserialization code, or sending around a bunch of unity packages and have one person do the integration.
Updated: you may want to review the UnityTextScene project.
A quick fix for this is to use Dropbox. It's not without its flaws, but it works for the most part (and supports things like revision control, deleted file recovery, and file change logs), plus, it's free (you can't beat that!). I've synced about 3 or 4 different Unity games of various shapes and sizes over Dropbox with no major problems.
We've been working with Unity in our small team here for a few months. The best way we found to work simultaneously is to compress the library folder into a .Zip file, and to commit it along with the Assets folder. On the local machine, you simply extract the library and open Unity. So you any modification to the code is controlled. You only need to create a new Library.zip once in a while, to integrate the settings made using the inspector. For example, if someone attach his new script to an object in a scene, if he does not commit a new library, it will still work but the script won't stay attached on your teammate's machines. So if that script is important for everybody's work, you just need to compress your library folder and replace the old one.
The worst thing that can happen is to obtain a conflict with the library.zip, but it is pretty easy to get around it by having someone integrate the modifications.
being able to find missing script components is useful, since if someone moves or renames a script, it can break the scene. See this script or this package.
saving out tweaked values of component properties is handy for quick movement of data from one person to another, available from the dump-to-file feature of this package.