I like the fact that all the cars look the same and it gives the marque an identity that you can relate to - no matter what model.
Plus, if you lie the look of one - you'll more than likely like them all - so the only choice you have to make is size of vehicle (and cost)
When a manufacturer changes the looks of a car it typically takes a few months (years?) to get used to the new design and quite often people dont like the new designs immediately and prefer the "old" shape.
However, after time, when you have become acclimatised to the new model - you look at the old model and think how dated it looks.
Manufacturers are always going to favour the look that appeals to the majority of people - so similarities are always going to occur......theres also the fact that the majority of manufacturers are all owned by the same group now anyway and to reduce R&D costs they are going to re-use designs across their ranges where possible. We no longer live in the days of multiple independent manufacturers :(