This release fixes a few minor bugs and adds a new, much-needed Reduce Noise effect. You can get it from the website (http://www.getpaint.net/) or via the built-in updater by going to Help -> Check for Updates. (Make sure that “Also check for beta releases” is enabled, by clicking on the “Options” button after clicking the “Check for Updates” menu item). Final release is tentatively scheduled for mid-January.
Changes:
- New: “Reduce Noise” effect.
- Changed: Ctrl+W will now close Paint.NET if zero images are open.
- Fixed: In Windows XP, when launching web content, sometimes Internet Explorer was used instead of the user’s chosen default browser.
- Fixed: Unfocus was not handling alpha values properly.
- Fixed: Brightness / Contrast adjustment was only displaying its text in English.
- Fixed: The /auto parameter for the installer now correctly allows for an automated installation. This was inadvertantly broken in 3.20.
paint.net blog 
Hey Rick, not sure if this is a bug or not, but I noticed that the installation takes far longer than 3.20
Ben – This might be the case because I turned on verbose MSI logging. I’m hoping it will help with troubleshooting. I also enabled “flush the file after every log event” so that might be what’s causing the performance.
I was curious of the long install too, but guess that must be the culprit.
The fact verbose has been turned on is usefull on Vista as you can follow an almost interactive install which calls both UAC and paintNet repair, plus an appcomp dialog. A pretty handy way to control the whole installation process. (3.22). And the additionnal time spent (about +5′) is really not a problem. Keep verbose MSI logging turned on M. Brewster, please.
This may be a little late (by about 20 hours over here in the UK) but here it is nonetheless:
HAPPY NEW YEAR!
Just had to inject some festive fun to this comment section. 🙂