On the cover it shows Lance on a bike w/ shifters on the downtube. I was kind of surprised, I thought the newer (especially TdF bikes) all had integrated shifters/brakes.
Here's a link for a picture:

http://www.amazon.com/exec/obidos/ASIN/0306814013/104-0553320-4887903

Any info for a newly addicted roadie, would be much appreciated!

LA uses a downtube shifter for the front ring during hill stages

So he has a STI shifter (is that the correct term?) for the rear der? Why just the front? What are the advantages?

My understanding is that it's a weight thingy.

I believe it is a weight and an infiinite trim thing. Searching this forum will give you whole threads on the subject. I believe that Marco Pantani started it.