No. A new kernel will be installed when the next Debian version is released. It will automatically update the kernel for you. However, you do have the option
of installing a newer kernel. Various methods exist, search the forums.
PS: 3.0.x is obsolete by now, the current (at time of writing) version is 3.6.6: see http://www.kernel.org/
If you are going to install a new kernel, make sure it's the latest stable version from the kernel.org guys.