The release announcement is here: http://blog.rstudio.org/2015/05/26/new-version-of-rstudio-v0-99/
Even though I’m relatively new to R and RStudio, from the moment I began using it, I felt that there were many features missing that one would normally expect from a “regular” programming language IDE. Quite a few of those have been added in this iteration. The nice people at RStudio have been regularly updating us about these in their blog, but only now is the final release available.