Last time I tried uploading a set of pictures using a curl script (not to flood maliciously, but to save me time getting the whole lot there) I got autobanned. Dunno how they detected it as I had changed the User Agent, but I noticed that curl sends and Expect: 100-Continue header whereas normal browsers don't. Maybe it's that.
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Anonymous2006-12-08 7:34
Isnt there that same switch in curl that wget has to introduce some randomness into the timing between operations? If say all your images got uploaded with 100ms between each one, it would look very suspicious.