read the full list of new features here
The most important changes in Notepad2 2.0.x compared with version 1.0.12 include support for ini-file storage of the program settings, modeless find and replace dialogs, multiline find and replace operations (using backslash expressions), optional file change notification, and many more.
There's also some regressions, i.e. ANSI code page support has been reduced to the system default, the bookmarks feature has been removed, a few syntax schemes have been dropped, and Notepad2 does no longer run on Windows 9x. If you need any of these features, you'll have to stick to Notepad2 version 1.0.12.
if you are still using Notepad, you might want to give Notepad2 a chance, is just as light weight as Notepad, but much more powerful