Well I learnt some things about RAP these days and I recalled a few things about eclipse I had forgotten as well I learnt new ones.
Part of the interesting things are targets in eclipse, which allow you to choose exactly the plugins available to the eclipse platform. This is particularly helpful when some packages conflict with each other.
In the case of RAP, the RCP and RAP plugins seems to have difficulty working together. I must admit though that I do not know what is the issue there.
So expect a RAP intro tutorial and perhaps other issues.