We've had success with the following:
candy from an local artisian chocolatiere, maple syrup, wine from CA and NY

And I have been told on good authority that the French can't stand maple syrup! A chaqun . . . .

Hmmm...where are you coming from? For Christmas, I would bring them some "dressed" beeswax Moravian candles (very pretty and easy to carry) and perhaps a tin of Moravian cookies...they're thin, not too sweet, go very well with espresso.
Or if I were in Phladelphia, perhaps I would hand create a calendar for them of "France in Philadelphia"...there is a lot shared between them...pictures of the Rodin museum, Joesph Bonaparte's House http://www.philaathenaeum.org/bonaparte/page1.html
Le Bec-Fin, La Colombe coffee shop (one of the owners is French) etc. You take the pictures, Kinko would make the calendar.
If you're coming from the Pacific NW, a small piece of Mount St. Helen's art glass...we've given that to Swiss relatives, they really liked it. Small, tactile, attractive, and connected to a major volcano.

Oops, the Bonaparte link didn't give his Philly address, which was 260 S. 9th Street. Last time I looked, it was still standing and was being used as an apartment building.

anything with american flags - baseball caps, t-shirts, fanny packs - will be greatly appreciated

Here is a picture of what the dressed Moravian candles look like. If you swan around the online shop, you may get some other good ideas.
http://shop.moravianbookshop.com/browse.cfm/4,84.htm

I think that when people travel somewhere they often buy unique (and often later regretted) souvenirs to remind them of their time there. French going to Texas may get carried away buying big belts and 10 gallon hats, but that doesn't necessarily mean they'd appreciate someone bringing them those as gifts.

Meanwhile, I'm really surprised not one person has suggested a bar of soap and a can of deodorant! (I'm ducking now)

oh yeah, right. I really don't think the idea of a Christmas gift is to treat other nationalities as if they are in some poverty-stricken place or that they don't have access to certain things. Really, I find the idea of giving cheap drugstore candy, junk food, trinkets, etc. as Christmas gifts to adults to be very odd. The idea of giving someone pancake mix, popcorn, etc. as a Christmas present is just bizarre IMO.

Maybe they like some unusual Texas hats as souvenirs, but that isn't appropriate as a Christmas gift. People have to think about what is good taste and this idea of being some trade ambassador is kind of weird, also, I think. Crystal platters, etc., are getting to be nicer.

As for CDs, again, this isn't some case of distributing bonbons to the poor locals. CDs aren't much different in price in Paris than in the US, and I bought some over there last month because they were cheaper than at home where I live in the US (and not only French CDs, but some current popular US ones, also). Virgin records has good sales, and you can get current CDs for about 10 euro that may cost US$18 at home as list price. Sure, that's a sale price at Virgin, and regular price in US, but it's the same thing in the US, you can wait until something is on sale.