It looks like HTC is keeping up with Windows Phone 8 update cycle rather closely, and has a device on its drawing boards which could be its first to ship with the software's GDR2 update version. Think of it as "service pack 2" for Windows Phone 8. The device is named (or at least codenamed) "Tiara," and is scheduled to arrive some time in May.
According to specifications leaked by @evleaks (UnviredView), the phone features a fairly balanced mid-range feature set. To begin with, it packs a 4.3-inch Super LCD2 screen, with a WVGA (800 x 480 pixels) resolution with a pixel-density of 224 ppi; an 8-megapixel primary camera with 1.6-megapixel front-facing one covering the imaging department; a Qualcomm Snapdragon 1.20 GHz dual-core SoC; 1 GB of RAM, 8 GB of fixed-storage, and an 1,800 mAh battery.
"Tiara" should slip into the lineup somewhere between the 8X and 8S.