This is the first I've really heard/thought about it, but we can extrapolate
some things about it based on the current plans for the desktop Clawhammer:
(Just my opinion...)
Hardware:
Pin-count increased from 462 to 754.
Integrated DDR memory controller
Integrated North Bridge
Hypertransport I/O Bus to AGP and South Bridge.
These will help simplify some aspects of motherboard design, as less
supporting components will be required; but also creates a revolutionary
change to the motherboard layout, which makers of mobile solutions can
sometimes be finicky about.
Also there might be some initial resistance in moving to a design that
is so different from current (Intel supported) standards.
Side note: According to the article at:
http://www.a1-electronics.co.uk/AMD_Section/CPUs/Hammer_Review_pg2.shtml
the integrated memory controller will only handle up to two unbuffered DIMMS.
Software:
32-bit performance is said to be equivalent with Althon XP, most analysts
expect actual performance to be increased due to improvements in data pre-fetch
and branch prediction designed into the CPU. Also due to the expectation that
Clawhammer will be released at a higher clock rate than existing Atlon XP and
MP chips.
The actual demand for 64-bit computing will rest on two factors: the
prior demand that will be generated for 64-bit on the Desktop/Workstation
machines, and the actual usefullness of 64-bit computing on mobile devices.
A lot of people will dismiss 64-bit computing on small form factor machines
because they will not forsee a need for the average user to have 64-bit;
but that will overlook the fact that a lot of scientific measurement and
field work depends on building small form factor devices into existing
measurement and analysis installations, and there will be a great demand
from that sector for tools that can handle ever larger datasets or
manage calculations with increased precision.
Timing:
AMD is probably planning on a Mobile version of the Clawhammer after they
have more time to optimize the fabrication process for the initial hammer line,
and to see if they can further reduce the voltage and heat for those processors
to accomodate conditions inside of laptop and mobile cases.
We might anticipate that the first Mobile Clawhammers will be released at a
lower speed than the desktop initially, possibly as another means to keep
heat and voltage requirements low.
I'm really most excited about the prospect of a dual Clawhammer desktop, but
the potential of a mobile x86-64 CPU is pretty interesting as well.