As Kevin notes , there are now more cell phone subscribers than landline subscribers in the US. My girlfriend and I are a good example -- two cells, no landline. The question, then, is how long before this starts violently skewing poll results. Pollsters are legally barred from calling cell phones. Cell phone users, to some degree or another, make up a different demographic profile than the rest of the country (skewed young and economically mobile), and may have different political opinions than the land users. This got a lot of attention in 2004 but, in the end, the polls turned out almost exactly right (indeed, those who harp on the exit polling forget that nearly every poll in the country got the results within the margin of error). As the country switches to cell phones, though, that won't last forever. So when's the tipping point?