This seems to pop up everywhere...
Hiring managers: “A good Linux-head is hard to find” | VentureBeat
Survey: Bosses are DESPERATE and GAGGING for Linux skills • The Register
DICE HOLDINGS, INC. : 2013 Linux Jobs Forecast: Pressing Need for Linux Talent | 4-Traders
Linux Professionals Receive Higher Salaries: Dice
Survey shows companies need Linux talent and they need it bad | ZDNet