I think we are comparing apples, oranges, bananas and mouldy socks here. Personally i think the 152 is a fine training aircraft and hard to beat. Some of the youngsters (Tecnam 2002 etc) come very close as far as handling and operating costs are concerned. Of course, they are also far more shiney and attractive to the new student. It is too early to tell if any of these take over from the 152 - on handling terms, there is no reason why they shouldn't.
Looking a little further ahead, I believe the 162 should
not automatically take over from the 152. Undoubtedly it will be well built and have a good support network but the figures appear to describe a decidedly average aircraft, doing no more than the 152 and far less than other LSA/VLA. I fervently believe that Cessna have made a mistake shoving a Continental in the front ahead of the Rotax. Maybe they know something about future fuels that the rest of the world doesn't? Either that or there is a Rotax driven 162 hidden in a hangar somewhere.
One final thought. Someone previously waxed-lyrical about the 172 - I agree. The 172 is a fantastic all-round, 'economical' aircraft (although I would still choose the 152 first for PPL training), most definitely deserving its place in history.