Added a point to "Which are the things I can work on?"

ImageSharp.NET-Summer-Hackfest.md

@@ -17,7 +17,9 @@ First, start by choosing what you'd like to do - you can have a look at [issues
 
 ### Which are the things I can work on?
 
-* [up-for-grabs issues](https://github.com/SixLabors/ImageSharp/issues?q=is%3Aopen+is%3Aissue+label%3Aup-for-grabs+sort%3Areactions-%2B1-desc) - There is sometimes a brief description how it could be implemented, but feel free to ask if anything is not clear, we will be happy to help.
+* [up-for-grabs issues](https://github.com/SixLabors/ImageSharp/issues?q=is%3Aopen+is%3Aissue+label%3Aup-for-grabs+sort%3Areactions-%2B1-desc) - There is sometimes a brief description how it could be implemented, but [feel free to ask](https://gitter.im/ImageSharp/General) if anything is not clear, we will be happy to help.
+* There are two big, hot and high-priority topics now: *(1) integration testing*, *(2) jpeg decoder*.
+We are constantly (re)evaluating the design needs here, so if you want to help with these topics, the best start would be to join our [Gitter chatroom](https://gitter.im/ImageSharp/General), and discuss the details.
 * If you'd like to implement your own feature, I'd recommend you to describe it first in an issue, so we can discuss it and help you with implementation. Sometimes the feature might be already implemented, but just have a different name.
 
 ### Project Setup