The same pros and cons that apply to doing that anywhere. Read the Learning Center articles first.
Also realize that Digg traffic is generally useless for income and unlikely to do anything beyond pumping up your stats for a few days.
Diggers can also be nasty and they aren't always the brightest people. If your hub can be misunderstood, they'll be the ones who will do it. If that happens with the first Digger and that one makes a bad rating, the rest usually follow like lemmings.
On the other hand, if they like it, you'll get a giant burst of traffic and maybe some legitimate links.
However - Diggers prefer to see your page recommended by someone who isn't you and that they trust..