The thing is, mortality rates are a lie. Why? Because they are based on the average of the whole population. What this means is, if you have a high child birth morality rate but your adults live to 100, you'll still have a low mortality rate. Russia has a 16.5 Infant mortality rate and it is a shameful fact for the country. But medication is improving and so is education (something that was lacking under the Soviets IRT birthing, etc) so the mortality rate will do a sharp increase over the next 5 years.
I don't want to get into a long debate defending Steyn's statistics, mostly because I have no clue where he got them, but MarMema's link provides life expectancy information (67 years) that is according to the US Census Bureau. Obviously, the US census bureau doesn't collect this information themselves and the link doesn't offer the actual source. UK Media indicates that the UN thinks Russian Men's life expectancy to be 61 years. The Russian Health Minister said in 2000, "Experts say drug abuse and sexually-transmitted diseases are potent new factors in declining male life expectancy, which has plunged from 64 years in the 1980's to less than 59 years today." Meanwhile, the Rand corporation said in 1997, "The Russian fertility rate has declined to among the world's lowest, while its abortion rate is the highest." That assertion is backed by facts and figures (http://www.rand.org/publications/MR/MR1273)
I don't see anything among the short searching I have done that fundamentally undercuts Steyn's thesis.