It does a hell of a lot more than what the propeller can. The chip they use has on-board ADCs and DACs, which makes it a lot easier to interface with analog sig

It does a hell of a lot more than what the propeller can. The chip they use has on-board ADCs and DACs, which makes it a lot easier to interface with analog signals out of the box. It also has a lot more RAM, DMA access so you don't need to use CPU clocks to pull things in and out of memory, support for pretty much any bus you need -- on-board USB slave and host, SPI, I2C, CAN, etc -- for talking to anything in the world. The Propeller was an interesting chip 6 years ago, but the world's more than caught up and surpassed it, with its only saving grace being that it's a cheap multicore chip, but even then, the XMOS chips are far more interesting there.