Beat me to it. Those that have changed their minds on the basis of the last five / six / eight games are the knee-jerkers, by definition.
The general trend under Martinez has been downwards, and he's GOT to reverse that trend. Now, the last five or six games MIGHT be the start of exactly that reversal - I pray to God that it is. But it is the very essence of short-sightedness to say "YES!!! The last five games definitively prove that the wealth of garbage results over the last 20 months are now a thing of the past!". He's got 12(?) game left this season - if this mini-revival turns into sustained improvement, as demonstrated by climbing the table to 8th and EITHER winning the Fa Cup or getting a win in the Derby then I would regard that as a corner turned on the simple basis that it's a bigger chunk of evidence.
He's got the squad to do it... I'd back first-season Martinez to do it. Time will tell, and it's entirely down to him.