Nope. Totally different.
As I understand it super basically, X-torq uses fresh air to blow out the burned exhaust gases before the atomized fuel from the crank is forced in through the transfers. Thus saving emissions supposedly as un-burned fuel is not coming out the exhaust.
From the Husqvarna Site Glossary
AutoTune
AutoTune technology uses a computer chip to control the flow of fuel to the engine. This enables automatic optimization of performance, which in turn reduces fuel consumption and emissions. The new chainsaw 576 XP AutoTune, which was launched in 2009 is a technological and environmental break through for professional chainsaws.
X-TORQ®
Husqvarna's latest technology for two-stroke engines, which reduces fuel consumption by up to 20% and emissions by up to 60%. The engine technology increases torque over a wider rpm range, providing maximum cutting power. X-TORQ® is used in E-TECH II engines for chainsaws, clearing saws, trimmers and leaf blowers.