For anyone who has ever watched their email inbox get buried by spam, the findings of a messaging vendor Tumbleweed Communications' study on email traffic that shows 83 percent of all email is actually illegitimate isn't all that surprising. But it should be. After all, in the first quarter of this year the percentage of so-called "dark traffic" was closer to 60 percent.

So what is responsible for that meteoric rise? Well, nothing breeds success like success and, it certainly appears that spammers have struck gold somewhere or we wouldn't be seeing the flood of spam. The report found said that messages to invalid recipients, most of which are spam, are 43 percent of incoming email traffic.

So why are spammers enjoying so much success? Simply put, as much money as businesses pour into their email infrastructures to handle the high volume of (mostly) illegimate traffic, enterprises aren't investing in the technology to stop those emails at the perimeter. Just something to keep in mind as you look ahead at 2006 priorities.