While Barry Allen will still be introduced in the upcoming eight and ninth episodes of Arrow season two, his full-on Flash-suited debut won't now happen in episode twenty but in a standalone pilot.
"Standalone" is Deadline's choice of word. They don't mean that the links with Arrow will be severed – the CW and their showrunners are keeping the two series as sharing the same universe – but that the pilot won't be an Arrow episode but the first Flash episode proper.
This seems to be a result of episodes eight and nine working very well. We'll see for ourselves in just a couple of weeks.
I guess we're to assume that this pilot, unless it's a washout, will herald the beginnings of a Flash series come next Autumn.
…nah. Those registrations were almost certainly made in preparation for Zack Snyder's new Superman-Batman movie; that's the reason why we'll be getting Nightwing lunchboxes, pyjamas and ice skates, not a spin-off show on a minority channel.