Need For Speed: Most Wanted marked a new era for the series. It was the first to feature a heavy, always-online component, and it was the last developed by legendary racing studio Criterion Games. Released in 2012, it's probably my favourite of the late NFS games, so it's nice that publisher Electronic Arts is giving it away to all Origin users as of now.
As part of EA's ongoing 'On The House' promotion, the game is free for a limited time. 'Limited time' in this case means, once you've acquired it, it's yours to keep, but you'd better do so soon because the offer expires. As for that, well, I don't know when it expires. You'd be wise to go and grab it right now.
Don't take my word for it: Dave Valjalo was positive in his assessment when it released back in 2012. "A smoother, more seamless ride than Hot Pursuit, it’s second time lucky for this fast, furious open-world motor show."
As for Ghost Games' 2015 Need for Speed reboot: the PC version is still scheduled for spring, which is autumn if you live in Australia and New Zealand.