omg: is Sylvester McCoy going to play Bilbo Baggins?

Screenrush.co.uk is screaming:

EXCLUSIVE: Sylvester McCoy Rumoured For The Hobbit

(Sylvester McCoy was, of course the last actor to play the Doctor in Doctor Who in the classic iteration of the series.)

But it gets a tad confusing once you get into the piece:

Loathe as we usually are to report on casting news before it’s made official, we simply had to tell you about this one. On a trip to the theatre last night (what you think we only ever watch movies?), we bumped into the venerable Sylvester McCoy, aka the Seventh Doctor, and were made aware that he’s been cast for a major role in The Hobbit.

Now we have to assert that this incredible tidbit didn’t come from the man himself but a close source has confirmed that he’ll be playing “the second biggest lead” in the upcoming Lord Of The Rings prequel opposite Ian McKellen and Andy Serkis.

The second paragraph here seems to contradict the first, or else that mention of running into McCoy at the theater is just a bit of name-dropping and has absolutely nothing to do with the Hobbit rumor.
But what is the “second biggest lead” in The Hobbit? Screenrush proposes that McCoy could portray

an older version of Baggins recounting the adventures of his early years.

I’d be delighted to see McCoy as Bilbo, but an older Bilbo narrating the film as “the second biggest role” in the film seems like overkill — the story simply doesn’t need such narration, and any framing story should neither demand a second actor (you just age up whoever is playing young Bilbo) nor require the second biggest role in the film.

Sp I’m confused. Unless someone considers Gandalf the biggest role and Bilbo No. 2?

(Thanks to reader Martha for the link.)