What are the photo gallery/album module choices for Drupal 7? I am looking to make a Flickr like site that user can create albums, upload photos. 
With Drupal 6, this can be easily done by CCK, Node Reference, Views. 

For Drupal 7, it seems difficult since Node Reference is not available yet. (There is a module called Reference, but in dev)

So are there any modules that can achieve the ugc photo albums functionality?

Thanks.
An album essentially is a grouping of like nodes.

In drupal this grouping can be done a number of ways. I would suggest using a fixed taxonomy (not free tagging) for the album. This way views can list list all photos (nodes) from a particular tag and you can create thumbnails for instance for display.

You could also group by author for another group of nodes (e.g. 'my photos')