Waiting on Apple Cellphone Call - WSJ.com

 I think it'd take Apple at least two or three releases to get a phone right, and it will likely take years to catch up to the level of scope and stability that Windows Mobile and Symbian have achieved. 

Entering the cellphone business likely would give Apple a huge revenue boost, which would be good for current shareholders over the long term. For the moment, however, the stock is trading at lofty prices, so now might not be the right time to jump in, especially if Apple disappoints Wall Street by not unveiling the phone next month or stumbles in rolling it out.

Source: Heard on the Street - WSJ.com