Both of those are nodes for the Guldencoin p2pool network. In effect, they create one pool together. However, individual nodes may perform differently; anything affecting latency can be a factor, such as geographic location, network latency, disk I/O, etc. In addition, fees are node-specific; guldenpool.nl (and node2.guldenpool.nl) is set at 0.5%, e-pool.net is set at 1%. Nevertheless, when you get a p2pool share, it is shared across all nodes, as is the payout table except for the block-finding bonus (0.5%) and the fee.
Now that the apt-named DELTA plan has succeeded, perhaps it's time to add some nodes? The p2pool network has been stable, but for dedicated mining it would be great to have some nodes in other continents. All three nodes are located in the Netherlands right now. It's not difficult to set up, so if anyone feels like it, let me know!
