Waypoints can have 32 characters for names and 256 characters for comments as of today. We'll be rolling a firmware update out soon to expand comments to 800 characters.
To answer Evshro & son, we chose 800 characters as a first pass at extended support for the geocaching details. We'll be making further improvements with each new release and hope to challenge all those multi-device cachers who carry a PDA with them when they are hiking.
Let me know if you have any other questions.
Thanks...
Chip Noble
Team DeLorme