Who knows? My only observations: The recent up-tick is consistent with price behavior during an economic recovery. And, even with the up-tick, the current year-over-year rate of inflation is in line with the down-trend that began in 1980.
Derived from U.S. Department Of Labor, Bureau of Labor Statistics: Consumer Price Index, All Urban Consumers – (CPI-U), U.S. city average, All items, 1982-84=100.
UPDATED 05/27/10: See this post for an alternative estimate of the rate of inflation.