SolidWorks 2010 Save Mod Docs notice
November 4th, 2009
With SolidWorks 2009 and any previous versions, when the user clicks on the X (exit) in the upper right corner of the SolidWorks window and they had a lot of modified files open, they would be presented with notice after notice asking if they wish to save, don’t save or cancel. It was very annoying. And, it was also nearly impossible to understand the relationships between the files being asked about.
SolidWorks 2010 has introduced the Save Modified Documents window. Now, when the user goes to quit SolidWorks, they are presented with a well organized window that shows all visible documents, with detail on how they related to each other.
The window offers the user several choices: save all of the modified documents, selectively save modified documents, don’t save documents, and the all important cancellation of the action to quit SolidWorks. (Sometimes when one sees what they are about to quit on, they will need to cancel the quit.) Oh, and don’t forget that Help button! 
With this new window, the task of quitting SolidWorks is now quicker and more predictable. I think this going to end up being on of these functions we will take for granted very quickly (forgetting just how annoying previous versions where in this).
[...] SolidWorks Video Tutorial: Two ways to loft to a point (pictured above) New in SW 2010: The Save Modified Documents window. [...]
how can i save a file in sw2010 so that i can open it in sw 2009??
SolidWorks files cannot be natively opened in down-versions. You’ll have to save your file as a parasoid and import it into the down-version. All history and parametrics will be lost in this process, as the model will be dump.