Sweave and .Rd files

Hello,

I found Sweave to be a very promising approach and in R-News 2003-2 
Friedrich Leisch wrotes about writing package vignettes.

There is another approach of Henrik Bengtsons R.oo package mixing R 
sourcecode and documentation, so I wonder if there is an approach using 
Sweave together with .Rd documentation files.

How does the development proceed in this field? Are there already 
practical experiences?

Thomas