RockYourPhone has released their v2 client. Now, I have not looked at this client yet. Let me state that I am not bashing rock your phone and have not made a determination yet whether or not it is great or terrible. What I can tell you is that if you are on a 3gs you should not install this until a 3.1 jailbreak is released.
As I already posted, the 3gs can no longer be restored to 3.0 or 3.0.1 anymore. If you update to 3.1 on your 3gs you may never be able to jailbreak again.
Rock your phone installs its own extensions and modifies a lot of system files. It is not installing just “an app”. They replace mobile substrate with their own version and the two may or may not work well side by side. Some thumb C function injection is likely to be broken. In normal cases, a simple restore would solve whatever issues you run into, but as things stand, you cant restore. So again, a very strong warning. If you are on a 3gs, do not install RYP2 at this time. If you want to test it, use a 2g, 3g, or wait for 3.1 jailbreak.
Note: this warning also applies to other software, but most stuff in cydia community sources can be repaired fairly easily without a restore using SSH.
Via thebigboss.org