I have just installed ubuntu 13.04 on my ThinkPad laptop. I am missing the launcher and upper bar. I only found references to the same problem for upgrades, so I tried everything written here, here and here with no success. However, referring to the second link, I ran ccsm and found my Ubuntu Unity Plugin unchecked. Checking it required to also enable the OpenGL and so I did. But, apparently I am unable to enable the OpenGL. Trying to enable it manually...and the checkbox gets automatically unchecked after few seconds.
Update: I have Intel graphics driver, maybe the problem is specifically with it?. I also tried running ccsm after logging using CTRL+ALT+F1 like given here. I was able to enable OpenGL and the Ubuntu Unity Plugin there, but still, no effect on my display, also after reboot.