According to early roadmap details we've seen, Intel is estimating that Ivy Bridge will offer a 20 percent performance advantage over Sandy Bridge which is slightly more than what Sandy Bridge offered over Intel's first generation of Core i processors. On the graphics side we'll see support for DirectX 11 and OpenCL 1.1 and Intel is targeting a 30 percent graphics performance boost compared to Sandy Bridge.
In addition to the raw boosts in speed, Ivy Bridge will offer DirectX 11 support; current Sandy Bridge chips only support DirectX 10.1. Ivy Bridge will also likely support PCI Express 3.0, three independent displays, and HDMI 1.4. So far, it doesn't seem to support DisplayPort 1.2; only version 1.1 is on the table.