The issue of RLink's incompatibility with R3.x is being worked on, and the fix is coming. You may expect it to appear in one of the following point releases. In the mean time, I will post any updates (such as if some temporary patches become available) here on this page, so stay tuned.

Thanks, inspired by your reply I tried the following on my Windows 7 computer. What am i doing wrong?

Needs["RLink`"];
SetEnvironment["LD_LIBRARY_PATH" -> "C:\\Program Files\\R\\R-3.0.3"]
InstallR["RHomeLocation" -> "C:\\Program Files\\R\\R-3.0.3"]

InstallR::fail: Failed to install R. The following error was encountered: Unable to load dynamic libraries >> tried the following on

Does anyone know if the problem has been solved in version 10. I was not succesful on my first attempts.