First, the bad news: your nuvi 200 just doesn't have enough free space to install the updated map data to the internal memory. Now the good news: you can either adjust the map update installer to skip a region of the map you don't use, or add an SD memory card and install the entire map set. The SD memory card must be at least 512 MB but not larger than 4 GB in size.

Amazon is sells SanDisk brand 1 GB SD cards for $6, which seems pretty reasonable. Like I said, you can use any SD card you've got laying around, as long as it's at least 512 MB and not larger than 4 GB.

1. Install Garmin's Map Update, either via electronic download or DVD-ROM
2. Decide whether you want to use an SD card and load all the maps onto the nuvi, or whether you're OK trimming unused areas from the map set. If you go with the SD card option, insert the SD card into the nuvi, and connect the nuvi 200 to your computer using a standard USB cable (the nuvi 200 doesn't include a USB cable, but you can use any USB cable, such as those used for digital cameras)
3. Open the MapInstall program (on your computer).  You can open MapInstall from your Start Menu > All Programs > Garmin folder.
4. When MapInstall opens it will ask you to select a device.  Just verify that the Nuvi is listed and select the "removable disk" from the drop down menu.  After you have selected the "removable disk", select Next.
5. Once the map page has loaded, simply select the states you want to install onto the card.  Be sure to remember that all of the states you originally loaded do not need to be selected.  You only need to select the states that were not included in the region you installed.

Yes - it IS annoying that the nuvi 200 doesn't have enough memory to handle the 2010 map update, and I agree with those of you who have suggested that Garmin should offer a solution to nuvi 200 owners that doesn't leave them feeling left out on the cold. Until then, the above steps can get you up and running.