The Haswell architecture is specifically designed  to optimize the power savings and performance benefits from the move to FinFET transistors on the improved 22 nm process node.
Haswell is expected to launch in three major forms:
(1) Desktop version (LGA1150 socket): Haswell-DT
(2) Mobile/Laptop version (PGA socket): Haswell-MB
(3) BGA version:
(a) 47W and 57W TDP classes: Haswell-H (For "All-in-one" systems, Mini-ITX form factor motherboards, and other small footprint formats.)
(b) 13.5W and 15W TDP classes (SoC): Haswell-ULT (For Intel's UltraBook platform.)
(c) 10W TDP class (SoC): Haswell-ULX (For tablets and certain UltraBook-class implementations.)
ULT = Ultra Low TDP; ULX = Ultra Low eXtreme TDP.
Only certain BGA versions will receive GT3 (Intel HD 5X00) integrated graphics. All other models will get GT2 (Intel HD 4X00) integrated graphics.
Due to low power requirements of tablet and UltraBook platforms, Haswell-ULT and Haswell-ULX will only be available in dual-core. All other versions will be available in dual- or quad-core variants.
Compared to Ivy Bridge (expected):
Twice the vector processing performance.
At least 10% sequential CPU performance increase (8 execution ports per core versus 6).
Up to double the performance of the integrated GPU. (Haswell GT3 vs Ivy Bridge HD4000)