Wow Steve,
What's there Month End reporting like (Item Valuation etc.) ? Are there enough trees left in the world for this or are you guys printing to electronic format ?
More on topic, I would add that with the prices quite affordable now, I'd be looking at Gigabit (1,000 Mbit) NICs and Switches with CAT 6 Cabling for the huge transaction volume implementations. With regards to existing Network infrastructure - once you're at a 100 Mbit minimum as Steve noted, the Gigabit technology can be phased in.