This could of course either be 1) a swerve a la Sophia Myles (which I'm still cryin' in my pillow over haha), 2) misinformation or 3) THE COOLEST FREAKING THING EVER!!!!
Now the source for this of course is IMDB, which can - on occasion - be wrong about things like character names.
It should go without saying that both these names - Susan as well as Tyler - are HUGELY loaded names in DW fandom. Add to that Moffat's comments that the new companion will be "a shock", plus that her name/identity are secret, and she can talk even faster than he does ...so of course you have everyone and their brother wondering - is this TenToo and Rose's kid, named after his beloved granddaughter? A kid was a part of RTD's potential head!canon for them (along with growing a TARDIS and traveling the world, per The Writer's Tale) - so on that front, it's plausible enough ...
Given Moffat's interviews over the past year or so (where he's mentioned Rose repeatedly), given the multiple videos/references of Rose in s5/s6, and given that the 50th anniversary will be Jenna's first year as companion ... and the fact that it's filming NOW, so any name leaks could easily come from call sheets ... could this be true?