It depends a lot on what field the patent is in, but less than 20% of utility patents take 5+ years to issue.  It looks like the average time has been about 3 to 3 1/2 years recently.<p><a href="http://www.patentlyo.com/patent/2009/07/patent-application-pendency-percent-of-applications-still-pending.html" rel="nofollow">http://www.patentlyo.com/patent/2009/07/patent-application-p...</a><p>This about 3 years old, but shows the differences between different types of patents:<p><a href="http://www.patentlyo.com/patent/2007/02/prosecution_dat.html" rel="nofollow">http://www.patentlyo.com/patent/2007/02/prosecution_dat.html</a><p>Software patents are definitely on the long side of things.