As some bros mentioned, these 2 cameras are really targeted for different audience.
S90 if were to compare with, should be LX3, EX1 or upcoming LX5 as they all uses 1/1.6 or 1/1.7" sensors with fast lenses.
If you keen in UW or Macro, long zooms should be on your list isn't it? However, EX1 seems to be very good at the moment, with sharp and fast F1.8 lens.
But do lookout for Panasonic announcement on 21st July on their LX3 replacement (LX5) which seems to be a mystery as of now of the size of sensor used....it was rumoured recently to use m4/3 ones which is very good but I would assume it should remain as 1/1.6" ones.
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