ARM and NXP believe the web can speed up the development of 32-bit microcontroller-based designs.
The move to from 8-bit to 32-bit processor-based designs, as represented by the take-up of ARM Cortex-M3 in the market, is bringing higher levels of complexity to embedded designs which has become an issue for MCU suppliers.
“When offering CPU performance of over 140DMIPs at 120MHz, combined with a range of peripherals like 
USB, Ethernet and CAN, it's equally important to offer increased ease-of-use and rapid prototyping capabilities,” said Geoff Lees, v-p and general manager at NXP.
ARM has set up a website to support prototyping of microcontroller-based systems.
Called "mbed" the website will launch with hardware and software support for the NXP LPC1768 
ARM Cortex-M3 processor-based MCU.
Intended primarily for early stage proof-of-concept designs, the first mbed microcontroller hardware packages an NXP LPC1768 Cortex-M3 processor-based MCU and support components in a practical 40-pin 0.1in pitch DIP form-factor.
There will be C/C++ Libraries to provide interfaces to microcontroller peripherals, based on an API-driven approach to coding.
The mbed.org website
See also: IAR introduces devkit of NXP's LPC1768 Cortex-M3 MCU