they are obsolente, but not because of display lists, but because of hardware changes..
with the time of hardware T&L (gf1 +, radeon +, etc..), the extension got quite obsolente, with the time of programable shadings it got even useless.. reasons unimportant..
at least: today we store our geometry at best directly on the gpu, and, placed there, we can draw it very fast.
to do so, i suggest to dive into the quite new ARB_vertex_object_buffer extension. it is about the fastest way to draw geometry.