The Tellme unit will become part of a "speech center of excellence" to be led by Zig Serafin, a 10-year Microsoft veteran. That unit will also include Microsoft's separate Speech Components Group.
The new unit has about 400 employees, with three-quarters coming from Tellme and 100 from the speech components unit.
"Mike has been instrumental in making Tellme a core part of (Microsoft's) long-term speech strategy," the company said in a statement. Microsoft "is on track to deliver this vision, so it's a natural time for Mike to move on to his next big thing."
Since becoming a part of Microsoft, Tellme's work has become integral to a number of parts of the company, including the automotive unit that works on Ford Sync, Microsoft's Live Search, and its Windows Mobile teams.
McCue is known for his focus on design and had talked about wanting to make sure his products were on both Microsoft and non-Microsoft devices.
"We want to be on every phone possible," McCue said in an interview last year.