> Ok, I'll bite. Not knowing a thing about ARM micros - other than that 
> they seem to be proliferating lately - how do they compare against pics 
> of similar memory size and pincount?

That, time will tell.
 
> What does 32 bits get you?
> 
> Mip for mip, are the ARM instructions capable of much more? Similar? If 
> a pic was running at 4 MIPs and one of these ARM devices was running at 
> 20 MIPs, is it 5 times faster? Or are the ARM mips more powerful?

http://en.wikipedia.org/wiki/ARM_architecture

Skip down to the C/assembly example if impatient. In short, theoretically the
address space is the same as that of a Pentium PC. 2^32 locations. This means
that you will never use paging or banking again, to store a puny 257 byte table.

> Do they offer ICSP?  I see high end stuff like JTAG.  Does one ARM 
> development system cover many devices?  Is there an IDE similar (or 
> better) to MPLAB?

JTAG is an industry standard that allows ICSP, ICE (well, a slow one anyway),
and much more. All this using only 5 wires with un-critical timing. JTAG is well
over 10 years old and there are very few surprises with it afaik.
 
> How do they compare to pics for writing assembly language code?

See above.
 
> What sort of peripherals do they come with?

Anything from two full 32 bit timers/counters + RTCC with 32kHz crystal to 3-4
network interfaces, zero to two wireless interfaces (Bluetooth etc), zero to
four (?) ethernet, two or more PWM/CCP channels, one or more I2C, one or more
SPI, one to eight U(S)ARTs, as many interrupt sources as you dare to dream up
and a proper stack so you can use a proper timesharing core and implement test
programs and debugging at your leisure over a serial terminal or whatever
instead of blinking LEDs.

Fully supported by the GNU toolchain (C language) for at least some of the cores
for now. Other compilers also available. Can program in HLL (C, Lua etc).

> What is the significance of the "Cortex-M3" name? Is it just hype or is 
> it some sort of improvement on regular ARM devices?

Don't know. The ARM that these people sell is the enhanced type with the Thumb
instruction set embedded. That's a way to write ARM-like code using 16 bits per
word instead of 32.
 
> Some of these questions might be answered by their data sheets if they 
> were readily available.  This outfit does not appear friendly - 
> registration is required just to see the data sheets...

The Wikipedia article is a good start. 

Maybe Wouter will write a little about it, he teaches this stuff.

Peter
 




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