Well a DP is an ethernet device.. a node. It is assigned an IP address either by the console or yourself. It depends on the network configuration. The DP processes the DMX. A Superwidget outputs DMX via USB and does not process anything. Now you can output upto 8 universes or DMX via 3PC or a full boar. This is because the internal DP on board the console processes the DMX and the Superwidget provides the output. Overall, the DP processes info keeping the network speed the same by adding more DPs when required and the Superwidget does not process anything.
Just to add to this, the DP will be connected via a corssover cable (or non corssover if a siwtch is involved) whereas a Widget will be connected by USB. So difference in speed may be an issue...
Does this make sense? If I am talking rubbish, somebody please correct me.
Well, the real power, as Joe said, in the DP is the out of console processing. Connecting a DP2000 or DP8000 to a computer takes strain off the computer's processing, and thus allows you to do a lot more with less. Plus, with the use of a DP2000, you can use it with a Hog3, Full Boar, and iPC consoles on top of the Hog3PC application. This allows you, if you needed or wanted to get a full-sized console for a show, to be able to connect it to any of the above mentioned consoles.
Also, as Lee said just above, the DP2000 will function as an ArtNET node, so that you can use it with any console or PC-based lighting program that will allow output of ArtNET direct. So this allows it to be used outside of the Hog family if necessary.
In my humble opinion, I think the superwidget is great if you know you never want to upgrade your system to more universes at all (or the max of 8 with 2@superwidgets); however a DP2000 or DP8000 will allow you the ability of greater flexibility.