If your iTerm or Terminal needs some time to start and the bash needs some time to appear if you create a new window.

Short solution is to delete the logs if they are to big:

sudo rm -rf /private/var/log/asl/*.asl

Here the source from os x …

I was using iTerm since I bought my Mac and was very happy with the tool. It is stable and worked well for me. It has nice features like full screen mode on Snow Leopard but after the update to Mac OS X 10.7 alias Lion the full screen …