22.9 percent of U.S. adults have a wireless phone at home but no landline.

• Two of every nine adults live in wireless-only homes as compared to two out of every 17 in 2006.
• Although wireless-only adoption rates for survey respondents decrease dramatically after the age of 35, every age group shows an increase in wireless adoption over prior-year surveys.
• The number of unemployed and retired adults using only a wireless phone has doubled to 20.2 percent from 10.3 percent since the midpoint of 2006.
• Even among households with both landline and wireless service, 25.7 percent of calls were on wireless telephones, and the CDC considers such households “wireless mostly” due to their increased reliance on cell phones. They account for 16.3 percent of all households, up from 14.4 percent in the first half of 2008.

And 75 percent of those between the ages of 12 and 17 own a cell phone, up from the 45 percent in 2004.

From: http://gigaom.com/2010/05/13/tracking-the-landlines-demise/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed:+OmMalik+(GigaOM)

AT&T’s numbers from late 2009 reveal that only 75% of all sold iPhones were in use. That proportion is declining every quarter. So its silly to suggest there are 85 million users of Apple iPhone compatible digital devices. If we use the 75% ratio from AT&T, the maximum is 64 million. In reality that is far below 60 million by now. Out of specifically iPhone models, out of 51 million sold so far, less than 38 million are in use (using same AT&T ratio).

From: http://communities-dominate.blogs.com/brands/2010/05/smartphone-wars-panic-at-apple-panic-at-nokia-google-stumbles.html

From: http://www.jiwire.com/downloads/pdf/JiWire_MobileAudienceInsightsReport_Q12010.pdf