A problem has started occurring recently in which some new files added to the subversion repositories don\'t get pulled down to other clients after doing an Update.
Known bug in TortoiseSVN 1.6.1: if you add an empty folder, the folder depth in your working copy will be restricted to "empty". You can work around this by updating once with the "update to revision..." dialog and selecting "fully recursive" as depth.
This has been fixed in 1.6.2.
edit: note that TortoiseSVN uses the SVN client library, which is where the bug was. The command line client had the same problem.
The only thing that I can think of is maybe it has to do with the 1.5 to 1.6 transition? Make sure everyone has a 1.6-based version of tortoiseSVN and try again perhaps.
Also, the way you are phrasing the question makes it sound like you are using SVN for distribution of files instead of concurrency. If that is the case, consider a tool like Unison instead of SVN.
I just happen to have the same problem. Here is a solution :
svn update `svn ls`
Yes, I know this problem is far from now, but it still comes up high in web search.