Flickr, via Yahoo!, says in its Terms of Service:
Yahoo! does not claim ownership of Content you submit or make available for inclusion on the Service. However, with respect to Content you submit or make available for inclusion on publicly accessible areas of the Service, you grant Yahoo! the following worldwide, royalty-free and non-exclusive license(s), as applicable:
With respect to photos, graphics, audio or video you submit or make available for inclusion on publicly accessible areas of the Service other than Yahoo! Groups, the license to use, distribute, reproduce, modify, adapt, publicly perform and publicly display such Content on the Service solely for the purpose for which such Content was submitted or made available. This license exists only for as long as you elect to continue to include such Content on the Service and will terminate at the time you remove or Yahoo! removes such Content from the Service.
(Section 9, incl. Paragraph B)
That "solely for the purpose for which such Content was submitted or made available" part is significantly different from YouTube. It seems like basically they're saying, if you upload your work, it's okay for us to display on the website... which is what happens when you upload your work. I might be wrong though.
The Blogger TOS says:
Your Intellectual Property Rights. Google claims no ownership or control over any Content submitted, posted or displayed by you on or through Google services. You or a third party licensor, as appropriate, retain all patent, trademark and copyright to any Content you submit, post or display on or through Google services and you are responsible for protecting those rights, as appropriate. By submitting, posting or displaying Content on or through Google services which are intended to be available to the members of the public, you grant Google a worldwide, non-exclusive, royalty-free license to reproduce, publish and distribute such Content on Google services for the purpose of displaying and distributing Google services. Google furthermore reserves the right to refuse to accept, post, display or transmit any Content in its sole discretion.
(From Section 6, emphasis in the original)
So they can use my work, but again not to the same extent as YouTube. Interesting.