[R] Learning advanced R

[Nik Tuzov]

Hello:

Could you please suggest the best way to become an "advanced" R programmer.
I went through "R for dummies" by de Vries and Meys and I can see two ways
to proceed:

1) Get a more advanced textbook. E.g. could you recommend Gentleman, 
"R for Bioinformatics"?

2) Because textbooks are limited and become obsolete fast, I can focus on learning state-of-the-art packages, 
but for that I need to find a list of most useful general purpose packages (foreach, doParallel, etc) that is
updated in real time. Does such list exist?

Your recommendations are very welcome.

Thanks,
Nik