Look at the Economy world wide before you decide that Rupee strenghened. The fact is that most of the currencies gained against USD. The current economic situation is US not so encouraging and slowdown is expected to be continued. This is one of the main reasons why Rupee is seems to be strenghened. Ofcourse, the Indian economy is improving and making strides. RBI used to intevene in the EX mechanism for strategic reasons, Now it has every reason not to intervene