But it's been more that a year and half since their merger and both the sites are still running independent of each other. Though Yahoo Photo users can sign-in to Flickr using their Yahoo! ID, they cannot transfer photos from Yahoo! Photos to Flickr or vice versa.
Now according to a Yahoo! Photos director, the workflow won't change anytime in the near future. Flickr and Yahoo! Photos will not be merged since these services appeal to a separate set of audiences.
However, the popular features of Flickr like tagging and simple sharing are being incorporated into Yahoo Photos. They will also release a Yahoo! Photos Uploader with drag-and-drop functionality which may be on the lines of Picasa Web Albums.
Flickr Not for Screen Captures, Download Flickr Photos (leech)
Source: Yahoo Photos and Flickr may grow closer