not for 'everyday' computing, but you will see a little bump in performance in gaming, rendering, and other heavy use applications. If all you are doing is browsing the web and doing office work you would not see a practical difference between an i3 and a i5, much less an i5 and an OC'd i5. I agree with Jaguar's prediction of 10-15% increase in heavy CPU applications, but no performance increase in general use applications.
For everyday computing (web, e-mail, anything other than games and production work) the biggest improvement you could make is getting an SSD, not a faster processor.