What tool would you recommend to automate several FTP uploads on a Mac? It should have a queue (so not all transfers are at the same time) and the ability to retry x times if the transfer fails. It should also be able to overwrite existing files without asking user confirmation, and report any errors.
I'm not sure what all options there may be for gui tools, but if you are at all comfortable with Terminal.app and the command line... I would suggest cURL might fit your needs. Actually, normally I'd suggest wget but it appears that OS X doesn't ship with it by default, though there are plenty of pages on the 'Net describing how to d/l and install it on a Mac if you really want it instead; the two (wget & cURL) are supposed to be functionally equivalent to some degree. Depending on what you want/intend to do... wget may be the better choice.