This morning's Guardian has an article based tonight's BBC Horizon programme - it states that Inmarsat believe the "hot-spot" is further south and west from the area that was searched.
This is the article ;
MH370: searchers not looking in the best place, satellite experts say | World news | theguardian.com
This is the key bit ;
"It was by no means an unrealistic location but it was further to the north east than our area of highest probability," Chris Ashton at Inmarsat told Horizon.
Experts from the satellite firm modelled the most likely flight path using the hourly pings and assuming a speed and heading consistent with the plane being flown by autopilot.
"We can identify a path that matches exactly with all those frequency measurements and with the timing measurements and lands on the final arc at a particular location, which then gives us a sort of a hotspot area on the final arc where we believe the most likely area is," explained Ashton."