Starting with the obvious: DC were planning on a media circus surrounding their controversial Death Of Superman storyline, and they certainly got it. A few years off revitalising the character's popularity with the Lois & Clark TV show, they didn't have much to lose and everything to gain in bumping off the Last Son Of Krypton. Reports of Kal-El's demise obviously turned out to be exaggerated, with the character returning to life a few months later with a new haircut/set of superpowers. The event itself was almost as disappointing, a match-up that didn't really respect the more interesting parts of Superman's character apart from punching things. The genetically-engineered Doomsday was created specifically to kill Superman, being equally as strong and nigh-invulnerable as the Man Of Steel. Many forget that Superman actually won their knock-down drag-out fight, before collapsing due to his numerous injuries immediately after so Lois Lane could have a little cry.
Tom Baker is the Comics Editor at WhatCulture! He's heard all the Doctor Who jokes, but not many about Randall and Hopkirk. He also blogs at http://communibearsilostate.wordpress.com/