Even through next day, or 2 day, or whatever shipping method was free, in my experience (yes, I have come across the exact same situation before), Dell won't charge you more, or cancel your order because of this.
Instead, what they did (to me at least) the last time was they simply shipped it ground. All it means is that you'll get it later than you previously thought. But better late than never!
Good business sense though, how many people would actually ring up and complain that their product was supposed to be shipped next day instead of ground shipping? They could quite easily turn around and say, well, if you don't like it, send it back. Besides, you didn't pay anything for the shipping, how could you complain?
Having said that, I wonder if Dell will make a bundle on these items. According to Canon, the MSRP is supposed to be 449 and 499 on the s200 and s330 respectively. But every other vendor shows MSRPs of 399 for the s330 (don't know what the s200 is, but most likely 349). If that is the case, this may not be that hot of a deal (comparatively).