Assuming Arrow executive producer Marc Guggenheim is being quoted properly, a new interview at TVLine has him confirming everyone's long-standing suspicions that Laurel Lance will indeed become the new Canary.
Here's what TVLine took away from their interview with Guggenheim. Bear in mind this is not a direct quote, so we could always get some equivocation from the writers and producers down the line here, but since TVLine routinely is one of the sites that breaks Arrow news, there's also no reason to believe they don't understand what Guggenheim is saying when he speaks [emphasis ours]:
Episode 3 will focus on dad-to-be Diggle, Episode 5 delves into Felicity's past (with NYPD Blue's Charlotte Ross as her mom), viewers will get to sit in on the limo convo between Malcolm and daughter Thea, and Ted “Wildcat” Grant (played by J.R. Ramirez as a Latino boxing instructor) will play a role in Laurel's evolution into Canary.
The Canary revelation, really, isn't surprising. Nobody involved with the show has done much to distance themselves from the overall impression that's where Katie Cassidy's character was heading. Nevertheless, this seems the first confirmation that she'll take up the mantle that her character does in the comics...and probably raises some broader questions about what that means for Laurel's sister Sara, the previous Canary who has ties to season-long big bad Ra's al Ghul.
There's been a lot of speculation that Sara might die, especially since there's an episode coming up titled "Sara" and had been earlier comments that she "looms large" over one of the episodes.