One of the most frustrating things with starting to use a new application is figuring out all the keyboard shortcuts that are available. Right now I'm giving Nambu a shot as a Twitter client. I'll admit I'm a bit of a power user of any app. I love me some keyboard shortcuts, but good luck finding a simple list of them in Nambu.
In fact if you're looking for actual documentation on Nambu your out of luck. Sure you can submit an idea/question through their Get Satisfaction list but if you just want to read general documentation, your totally out of luck. I guess they have a help section accessible from the desktop menu but it's entirely useless.
Why is it that developers of software are skipping this vital part of building great software? I know documentation isn't sexy but it's vital. Written software is only half realized to your user without solid documentation on how to use it.
Here's a challenge developers, write proper documentation. If you're 'agile' then use a sprint to work only on documentation. If you do that every few sprints then your documentation will be solid. Good software is more than just the code that runs the application, it's your customer service, and documentation. Start building good software.