At the same MHz, both of these CPUs will perform exactly the same.
The different is ECC (error correcting memory bits) on QPI memory bus of Xeon.
Xeon processors are intended for servers and workstations, while Core i7 processors are for desktop PCs.
Core i7 features a better virtualization and digital media experience, which supports photo creation and publishing, video encoding and more complex games
Xeon is a successor to Pentium II, while Core i7 is a successor to the Core 2 family