As part of the big rewrite, all of the SRD spellcasters are being rewritten as well. The narrower classes are being made broader to suit the fact that their other cousins tend to be quite broad as classes. Additionally, quite a few oddities have been corrected, and classes have been created which (I hope!) work well. At the same time, I realise that not everyone likes broad classes, and that's OK. For alternatives, check out Chapter 5: Variants and Variations, which gives a range of narrow classes to suit many tastes.