An app by Phototheca
This is the desktop photo organizing software for Windows - Phototheca (lunarship.com). Phototheca has the feature to upload photos, Albums and Events to Flickr, into new Sets or Photostream under your account. Just in two clicks! You are able to specify privacy level and size of uploads as well. Phototheca can perform 2-ways synchronization with Flickr, meaning all your changes made to photos locally or on Flickr appears on opposite side. And all metadatas(EXIF, IPTC, etc.) are preserved on upload as well!