Was looking for solution to control many (>100) LEDs (many of them white or blue) and decided that PCA9673 is best solution.
I've attached a driver that seems to work (input mode not tested) [See Attached]
Great things about PCA9673 are:
small surface mount package (sorry, no DIP), and 16 outputs with just 2 Prop Pins
5V tolerant outputs (lets me drive white/blue LEDs with +5V and series resistor to control current)
Up to 16 devices on I2C bus with just 2 address pins (neat trick they pulled off here!)
Can sink >20 mA on all output pins at the same time!
Super simple I2C commands
Can work up to 1 MHz (but my driver is rigged for 400 kHz) (fast enough to allow digital dimming)