Intel's first entry to the smartphone market has had limited success so far, but yes, phones with the Medfield chip have started shipping. Tests have shown that the single x86 core can match some recent ARM based chips in terms of performance and power drain. However, Intel believes that chucking significant amounts of processor cores at tasks is not the solution as they believe Android is not ready for multiple cores. Instead they believe further optimisation is more important, and that this could originate from chip manufacturers such as Texas Instruments and Qualcomm.
Intel's Mobile and Communications Group General Manager, Mike Bell, had this to say:
“If you are in a non-power constrained case, I think multiple cores make a lot of sense because you can run the cores full out, you can actually heavily load them and/or if the operating system has a good thread scheduler. […] So as we move to multiple cores, we're actually putting a lot of investment into software to fix the scheduler and fix the threading so if we do multi-core products it actually takes advantage of it. […] The way it's implemented right now, Android does not make as effective use of multiple cores as it could, and I think – frankly – some of this work could be done by the vendors who create the SoCs, but they just haven't bothered to do it.”
KitGuru says: We haven't gotten our hands on a Medfield based phone just yet but we're interested to see if these claims ring true.