Some of Intel's cheapest dual-core CPUs will now have four threads enabled rather than just two [tomshardware.com], in what may be a move to compete with AMD's upcoming Ryzen CPUs, which all have two threads per core:
The Pentium series traditionally consists of low-power, dual-core offerings with no [Hyper-Threading (HT)]. Pentiums serve as the low-end alternative to the i3 series, which features dual-core offerings with HT enabled. The addition of HT to the Pentium series expands its range, but there are still a few key differentiators compared to the i3 series.
[...] The HT-enabled Pentiums create a challenge to AMD's line of low-end processors, and of course, some will speculate that it appears that Intel is bolstering its low-end products in the face of AMD's pending Ryzen onslaught [tomshardware.com]. In either case, the HT-powered Pentiums add a welcome new wrinkle to the low end. The processors are listed on Intel's ARK [intel.com] but are currently available only for preorder.