The use of aluminum in vehicles is an engineering development by manufacturers in response to government-mandated CAFE (corporate average fuel economy) requirements. Aluminum is a the most cost-effective material to reduce weight while maintaining the necessary structural rigidity and strength in vehicle chassis and body design. Ford's use of aluminum, however, is also a response to get its weight down to match (finally) Chevy's trucks weight with the use of its proprietary high-strength steel. As mentioned, there are several drawbacks to aluminum's use in vehicles, the most significant being initial cost of material, and hence, the vehicle purchase price, and as stated in previous posts, the maintenance and repair issues associated with aluminum.
To me, however, a much bigger cost (and problem) is the corrosion factor and the need to protect aluminum from oxidation. Aluminum will lose its strength due to corrosion much more quickly than steel, unless properly protected. Durability and longevity is an issue, especially when a new truck is now in the $40,000 range and a new vehicle loan is in the 72 month (6 year) length to make its monthly payments affordable to the new vehicle owner. You would like the vehicle to outlast the length of the loan.
So what does this development mean to detailers? New paints and coatings for aluminum panels will probably be developed, requiring new care-car products to be compatible with them. I am guessing this will happen.
Most cars built in the last 20 years have aluminum parts within the engine compartment. Any detailer/hobbyist/mechanic knows the white corrosion that forms on these parts and having to deal with those issues. Don't even get me started about using OCT Simple Green (and other caustic APC's) as a degreaser and its effect on aluminum. It will mean those of us who clean/detail vehicles, whether for fun or for profit, will need to be more vigilant about the products we use on newer aluminum-built vehicles, if we are not already.