Since there seems to be a lot of us in the same boat with this here issue, can you tell us if you've released a newer build after 16.4.29, one that would work with Snow Leopard (especially the 32-bit version)?
Also, is Dropbox about to drop support for 32-bit OS X, or was this just a case of bad build?
Just received this from Dropbox Tech Support. Haven't tried it yet, but thought I'd share it in case it can be of use to you.
Re: Ticket #5217322: DB: Can't start up Dropbox on one of my computers (my iMac) Luke, Dec 21, 11:41 AM PST:
"Hi, The development team has released a new beta version of the Dropbox desktop application that may resolve the issue you are experiencing. If you would like, you can download this version of the Dropbox desktop application from the following link: https://www.dropboxforum.com/t5/Desktop-client-builds/Beta-Build-17-3-28/m-p/199007#M3559. If this resolves the issue, you should be able to continue using this version as it will update automatically to the next available build going forward. Please let me know if the issue persists after installing this version. Thank you. Regards, Luke