NYSE Group is the public company that emerged from the merger of the New York Stock Exchange with Archipelago in March of 2006. It became a division of the InterContinentalExchange (ICE) when ICE acquired NYSE Euronext. Euronext was spun off from ICE in early 2014 and NYSE Group remained with ICE.
On January 29, 2015, NYSE Group announced that it would begin the rollout of its new trading technology platform, called Pillar, in the second half of 2015. The platform will enable customers to connect to all of the group's equities and options markets using a single specification. The NYSE Arca stock exchange will get it first, in the third quarter, followed by other markets including the New York Stock Exchange, NYSE MKT, NYSE Arca Options, NYSE Amex Options, Global OTC and NYSE Bonds.
NYSE Group Timeline: http://www1.nyse.com/pdfs/nysegrouptimeline.pdf