Intel's latest mainstream processor architecture isn't a massive upgrade but Haswell does boast some performance gains, new/refined features, and improved energy efficiency, the latter most useful in the mobile chips running Windows 8.
You do software updates to get the most from favourite programs right? Updating a motherboard BIOS can in a timely manner is also critical. The guide to Flashing a Motherboard BIOS spells out the often complicated steps in plain english. PCSTATS Tips