I've developed in IntelliJ IDEA for several years. And I've never seriously used NetBeans or Eclipse.
But now I have to work in Eclipse and I want to be able to use at least part of its power as soon as possible.
So, the question can be divided into 2 parts.
1) More general question: how to learn new IDE in a short time?
2) Are there any extremely good Eclipse tutorials? Like '30 things Eclipse developer must know' or something similar.
Here is a comprehensive keyboard shortcut list for Eclipse.
When I'm learning something new, I like to keep shortcut documentation or function lists (if learning new libraries) up on my screen all the time. I read through quickly once or twice to get a feel for what's possible, and then as I'm working when I find a use for a feature I remember, I then look back at the doc to see what I need to do in order to use it.
This isn't a direct answer to either of your questions, but Mylyn is an extremely useful plugin. Of everything I love about Eclipse, this is the best tool in the IDE for me.
Just start using it. Each time you run into a task that you know how to do in your old IDE, figure out how to do that one task - say, by hunting through the menus, Googling, or posting on SO - and then keep going.
Changing the IDE you use can be compared to changing the language in which you program... seriously in my view yes, The productivity of the developer is directly dependent on the familiarity of the IDE he is using.. To answer your particular question,
-> Use the key binding of the IDE which you are familiar with on the new IDE so it will give you a quick rampuptime and you can import the existing projects to new IDE version using some plugins.
-> Eclipse help will be a good starting point for you as you had good experience working with Intellij.
Being a user of both the IDE's, Eclipse inherits most of its features from Intellij (As I guess the people who developed eclipse used Intellij to develop it).
I try to learn one feature each day.
I tend to remember them better when I have used them instead only read about them.
Whenever I learn anything new, I find it helps to skim through a book in one evening and just start using it. The Ecłipse IDE pocket guide should do the trick even if it is a few years old.
Start by writing a small app in it. Do a 'Hello World' type thing and then start adding to it bit by bit. Maybe write to a file, or display a simple GUI or menu.
If you're interested in making the key bindings match, just watch out for spending too much time defining every last key combo before actually using the IDE. Unless it already has a binding profile (aka Emacs or Brief), configure the top 5-10 commons ones and after that add keybindings one at a time as the need arises.
A good way to learn an IDE is to practice small programming tasks a la code katas. By working on a problem that you know how to solve, you can focus on how to write the code more quickly by using your editor more effectively. Not having to think too much about what code to write allows you to free your mind to focus on new ways to get that code written.
Unplug your mouse. Every time you want to use a menu item of any sort, learn the keyboard shortcut, instead.
Pair. It's the fastest way to learn a language, the fastest way to learn domain, and the fastest and best way to learn an IDE or other tooling. And it's fun and productive, too.
When pairing, you witness the features of the IDE in use, and when something cool catches your eye, you ask: "What was that?" Your pair answers, and now you know a feature that's cool and useful to you. Far better than comprehensive lists of features, only some of which are useful; far better than dummies books or solo practice. For users new to an environment and for old hands, this is a great way to learn the important things about your tools. Pair.
There is a great set of eclipse tutorials on sourceforge http://eclipsetutorial.sourceforge.net/totalbeginner.html
The tutorials are geared towards beginners to both eclipse and Java but skippng through them should still be of great help.
They can be difficult to open though. I just open them using Firefox.