Mapsource & numaps update

Preview: Older maps in Mapsource from dead GPS + free upgrade for new nuvi = ?

First... sorry if this has been answered already... I waded through some of the 1300+ responses to the Map Upgrade thread and an answer to my question didn't jump out at me.

Short Version:

I have CN North America NT 2008.9 maps on my PC from a now dead c340, and just bought a nuvi 255W for which I'm entitled to a map upgrade before January. Will the map upgrade affect just the unit, or will the maps in MapSource be updated also? If just the unit, has anyone asked for and received a map disc from Garmin for maps pre-installed on a unit?

Long Version:

Sadly, my StreetPilot c340 unstuck itself from the windshield, hit the dash (from about 1" up), started complaining about being low on battery despite being plugged and (supposedly) receiving power through the cradle, turned off, and wouldn't turn back on. Plugged it into my PC via USB, and while it would emit a faint high pitched noise, it still wouldn't turn on. It's dead, Jim!

Sooooo....

I bought a nuvi 255W, which is eligible for a free map upgrade. What I noticed right away was that no CD/DVD accompanied the unit. When I plugged it into my PC, MapSource (v 6.15.7) recognized it and let me send my waypoints (and routes, despite the 255W apparently not being able to use routes) down to the unit. That was nice since we were visiting my youngest son at Rider U in NJ and we live in VT.

Here's the question, which I can't seem to find an answer to. My c340 came with City Navigator North America NT 2008 v9 maps on it. The 255W came with CN North America NT 2010.10 on it. I'm thinking it would be really nice if the maps on my PC matched the maps on my nuvi. When I download my free update, will the maps in both the unit and MapSource be updated? If not, has anyone asked for and received a disc of the maps that are on the unit?

Thanks!
Geoff