NCBI has released "Try Our New, Experimental PubMed Search and User Interface in PubMed Labs."
Here's an excerpt:
NLM needs your input. We are experimenting with a new PubMed search algorithm, as well as a modern, mobile-first user interface, and want to know what you think. You can try out these experimental elements at PubMed Labs, a website we created for the very purpose of giving potential new PubMed features a test drive and gathering user opinions.