Photography: is it art?

Andreas Gursky's Rhein II fetched £2.7m last year, setting a record for any photograph sold at auction. Photograph: Andreas Gursky/AP Photo/Christie's

Another great photography event coming:
Seduced by Art: Photography Past and Present
National Gallery, London, WC2N 5DN

Michael Prodger from Guardian provides sophisticated prospect yet I found this article remarkable for comments and my favourite is:
ArundelXVI 
Photography most certainly can be art. My problem with so much contemporary fine-art photography is that so much of it seems like bloody snapshots. Without much aesthetic consideration for form and colour. And blowing the picture up to near-mural size does not add profundity.