Mac OS X 10.7 Lion Review:
Also gone is "Rosetta", the brilliant little code translator that allowed existing Mac applications to keep running when Apple switched its Mac products from PowerPC to Intel processors just five years ago. Considering that many widely-used applications, such as Quicken 2007, still haven't been ported to Intel, this is a serious problem. If you depend on PowerPC-based software of any kind — from older versions of mainstream applications sold by companies like Microsoft, FileMaker and Adobe, to Apple's own USB modem, to PowerPC-based drivers for scanners and printers, Lion is not an option.
Worse, Apple hasn't breathed a word about any of this to customers other than developers. Not on the marketing website, not in its support pages, not even buried in a tiny footnote somewhere. Any Mac user with older applications who upgrades to Lion may be in for a nasty shock when their tools suddenly stop working.
There are many thousands of older, specialized applications which are still critically useful to Mac owners today, even though they have not been converted by their developers to Intel-based code. Similarly, there are untold numbers of Mac documents that are readable only by software incompatible with Lion. While Apple may recognize no duty to support these older Mac technologies, it absolutely has the duty to tell its customers that its removal of an existing Mac technology will suddenly disable their software and documents. Apple's silence on this change is unconscionable.