Raspberry Pi interview: Eben Upton reveals all (Linux User)

> Not everyone is going to need a serial port so why make everyone pay the extra cost for the part and pick/put robot placement on the board plus the increased board size that it would require?

Right, that's why you don't want to compare a 35$ "development board" with an 89$ Development Board (capitals and quotes intended.)

Even if your 5$ price increase would be accepted at face value, you still haven't factored in the cost of a proper JTAG connection.