While it's still a teaser at the moment, John Nack (Senior Product Manager for Photoshop) has confirmed the development of Photoshop Express. It's a free online photo editor that's not meant to replace Adobe's current offerings, but "make Adobe imaging technology immediately accessible to large numbers of people".
http://blogs.adobe.com/jnack/2007/09/photoshop_expre.html

Premiere Express isn't available as an end user product from Adobe - they only sell it to some of their partners who implement it on their sites.
http://www.riapedia.com/tags/premiere_express

Its a good news that Adobe is coming up with this free version of photo editor. But honestly, you can't do alot of things with it since its meant for touching up photos. Not like the Adobe Photoshop that you can use to design graphics. Will still stick to picasa if its just for touching up photos with instant uploading of them. But its still something worth a try from Adobe.

With the new applications online that are been leaving, I believe that it marinates has been entered to a market that is controlled in greater part by our great friend Google one of the pioneers in the implementation of the tools online. And in addition it is not or it will be the unique service of this type so that already there are many like:

http://www.wiredness.com/
http://www.fauxto.com/
http://preloadr.com/
http://pixenate.com/
http://www.phixr.com/

For Adobe it's just market sense to move into the online world.. Google seems to be snapping at the heels of just about everyone, and the sooner you can establish yourself as a player the more brand awareness you create. Especially in the case of such a large company as Adobe, the buzz will get out pretty quick, and if they're serious about grabbing a share of the online visual editing market, they'll provide something that has unique features that the competition doesn't offer. At least that's what I hope they're thinking...