Mileage Plan credit card
What is the maximum bonus that one can earn by getting a MileagePlan credit card? The online application form I saw seemed to indicate 30K miles and a $75 annual fee - is that the most one can earn (seemed somewhat low compared to other airlines).
Also the application seems to be rather vague as to which card one can get - the Visa Signature card or the Platinum Plus; the terms & rewards for the latter are not spelled out online. Does anyone know what the sign-up benefits of this card are?