I intend to use MySQL as my database of choice for web applications. I have been using Textmate to develop Groovy / Grails applications, but Netbeans V6.5 (RC) now supports Groovy and Grails. I can't quite bring myself to move away from the simplicity of Textmate but will check out Netbeans 6.5 as it matures.
Go to the www.netbeans.org website for the latest downloads. I installed the Netbeans + MySQL (Version 6.1) bundle first - this is a quick and simple way to get going with MySQL (Don't forget to install the MySQL preference pane). Then I downloaded the Version 6.5 (Release candidate). Just follow the instructions; if only everything was this simple.
Note: You will need to set Groovy Home in the Netbeans preferences (Miscellaneous/Groovy) to /Library/grails-1.0.3
For a good introduction to Groovy and Grails take a look at Jason Ruldolph’s (free) PDF Getting Started with Groovy and Grails.
Other essential reading is Beginning Groovy and Grails by Christopher Judd, Joseph Nusairat and James Shingler and The Definitive Guide to Grails (Version 2) by Greame Rocher and Jeff Brown
This looks interesting. Sproutcore is a framework for developing desk-top like applications for browsers. It has been used by Apple on their Mobile.Me application. Take a look at www.sproutcore.com.
I will report back when I have used it a bit more, but in the short term I am not sure if a have a real use for it.