Lara Croft And The Guardian Of Light will be a digital download released, presumably, on the Playstation Store. Though we've not been told concrete platforms as of yet.

Apparently, the game's going to be completely different to what you might expect.
[quote]
“This is a really exciting project for Crystal Dynamics, we have created something completely new and very different to what people might be expecting,” said Darrell Gallagher, Crystal Dynamics boss.

“Lara Croft is such an iconic character in videogames, with Lara Croft and the Guardian of Light we have created what we believe is a truly original digital experience.”</blockquote>

It's going to be shown in private at GDC next week. Some really old rumours suggested Lara had gone all survival horror. We'll have to wait and see if that turns out to be the case.