Details on new Doctor Who companion Jenna-Louise Coleman are reportedly due to be released soon, including her full name.

Steven Moffat has apparently recorded an interview to be broadcast on BBC Radio 5. In it Moffat explains that:

→ The new companion will, again, be a human from contemporary earth. This is necessary for audience identification and a ‘jumping on’ point for new viewers

→ How the companion gets where she is and what that means for the character is what will make her utterly different and fascinating

→ The new companion will not have any links to any previous characters

→ Her ‘journey’ will be shocking and intriguing. The Doctor has never met anyone quite like her before

→ Her very presence in the TARDIS will change the Doctor and there’s something different about her that will have a knock-on effect for the Doctor/companion dynamic

(source)