I would like to use FreeRTOS on Philips LPC2148 as soon its released. This chip has an on board USB. Will FreeRTOS support this Hardware with an USB Stack? Are there other Stacks running with FreeRTOS?

USB ‘device’ drivers are generally easy to write and a complete stack can be wastefull on small memory devices. Have you seen the atmel SAM7 (also ARM7) FreeRTOS port?  This includes a sample driver for the on chip USB device peripheral.  I have seen on the SAM7 Yahoo group somebody has modified the supplied Joystick driver to make a USB to serial port converter driver. Have a look at the SAM7 port documentation on the FreeRTOS WEB site.