Everyone should not cancel their order but just refuse shipment if the total was changed without your knowledge. They should pay for trying to scam people. Even smaller companies at least call and give you the chance to accept the orders. As far as that CSR not caring if you go with Dell or not, she'll care when her butt is in the soup line. They must get the sales reps that Staples fires.
I remember when Gateway would jump through hoops to keep customers. No wonder they are going under, their sales reps would rather be home watching soap operas.
Another thought on this. Accept the computer, and if they overcharge you, file a complaint with your CC for an overcharge and fax them the email confirmation and quote. You should not pay more than you agreed to.
If this was just a pricing error, and they informed people they would not be getting their orders, I would be the first to defend them. However, to do some as sneaky as sending them out and charging a different price, that's major BS. I hope this is the final nail for them.
Okay, I'll quit ranting for now. :|