I think the Leeds era of prominence is probably coming to an end as others have done before them.
In the 14 years of professional superleague, Saints have been more or less at the top of the pile over this whole period. Seem to remember our challengers came in the form of Wigan for a season, Bradford Bull for a couple of years, Hull for a season, Leeds for a couple of years.......and possibly Warrington and Wigan in the future. Yet Saints are still very much a threat season after season.
Leeds and Warrington have quite a lot of players around the 30+ years mark, so in 2012, Leeds might struggle having the next crop of players in place, where as Saints could be in a much stronger position, hopefully.