Not really. For instance, with TiddlyWiki you can run a local server and save everything on disk in a single html file. Jumping from localStorage to a DB means you go straight from "only in one browser" to having to deal with the overhead of a DB. A single text file has the advantage that you can drop it in a repo and have it version controlled or keep it in a Dropbox folder and use it on multiple computers/share it with others.
