To make developers’ lives easier, Apple *really* should make the following 6 frameworks bundled with their OS, it will make application distribution much better.
* [Growl](http://growl.info)
* [Sparkle](http://sparkle.andymatuschak.org)
* [Perian](http://perian.org)
* Universal Charset Detector
* A decent HUD framework (maybe based on [HMBlkAppKit](http://shiira.jp/hmblkappkit/en.html))
* A decent Tab control (maybe based on [PSMTabBarControl](http://www.positivespinmedia.com/dev/PSMTabBarControl.html))
我建议还要加：
regular expression, md5/sha1, base64
还建议把 chinese calendar 尽快做好。 japanese calendar 都做好了。
感觉 growl 没必要，说是免去了点击“确定”的麻烦，但是许多现在软件用的那些提示，也很烦人，完全没有必要。
@nanmus: regular expression 支持在 POSIX 中已有，系统自带。md5/sha1, base64 支持在 openssl 中已有，系统自带。