Predicting life expectancy of people currently alive, can, of course, only be speculation, but one based on statistics. If there is a nuclear war next year, the predicted life expectancy will not be accurate.
For the United States, the CDC estimated a life expectancy of about 80 for children born in 2013 (table 16). 71 is the estimated expected life span at birth by the WHO for children born in 2012. This includes all countries.
However, these are medium values (often medians, meaning half of all people will reach a higher age), and people getting over 100 years is certainly not unheard of, even today. In 2012, there were over 300,000 people alive who are over 100. The US had over 7,000 of them alive in 2011 .
As for predictions for over-100s: For the UK, one third of babies born in 2013 are expected to live to 100.