There are a number of bugs marked duplicates of this bug that really aren't. The size of /boot is orthogonal to the issue of purging unused kernels. 256 MB gives the ability to install approximately 4 kernels. For some of us that's not enough, and we need to specify a larger /boot. Shortly, I intend to unmark 1465050 as a duplicate, and mark 1511911 as a duplicate of that.
There are a number of bugs marked duplicates of this bug that really aren't. The size of /boot is orthogonal to the issue of purging unused kernels. 256 MB gives the ability to install approximately 4 kernels. For some of us that's not enough, and we need to specify a larger /boot. Shortly, I intend to unmark 1465050 as a duplicate, and mark 1511911 as a duplicate of that.