On the first of the upcoming year, Port Seraphine will close down, and PixelDolls as well, along with the Gallactic (I checked; that's really the spelling), Romance, and Chroma shops. Until then, all items are going for L$50, and there will be a special limited edition last item.
I am happy to say that Nephilaine Protagonist isn't leaving SL, and will still be doing things.
For me this is kind of like Goldie Locks going away; I have a LOT of items from PixelDolls. I use the skirts from the Bourbon outfits a great deal, as well as many of the PixelDolls tops that lend themselves to easy adaptation to prim breasts. Thank you, Nephilaine!
For more details on what's happening, including things to commemorate the event,. take a look at this thread on the SLUniverse forums.