Well the thing to consider is that the user based feed URL is of the form:
http://picasaweb.google.com/data/feed/api/user/ashish.vashisht/albumid/5128196317222632433?kind=photo&alt=rss
Hmmm... seems like an attempt to masquerade a get parameter as a URL. Let's try stripping the albumid and the album id (pun intended) from the URL
http://picasaweb.google.com/data/feed/api/user/ashish.vashisht?kind=photo&alt=rss
Sure enough! Works!!
Now, how to get the Picasa slideshow thingie to show this?
Lets see the code:
<embed type="application/x-shockwave-flash" src="http://picasaweb.google.com/s/c/bin/slideshow.swf" flashvars="host=picasaweb.google.com&RGB=0x000000&feed=http%3A%2F%2Fpicasaweb.google.com%2Fdata%2Ffeed%2Fapi%2Fuser%2Fashish.vashisht%2Falbumid%2F5128196317222632433%3Fkind%3Dphoto%26alt%3Drss" pluginspage="http://www.macromedia.com/go/getflashplayer" height="192" width="288"></embed>
What we have to do is alter the feed= part to something relevant... One way to do this is to URL Encode it... Not very eays to do unless I write some code... Alternately, just search for the feed URL at Google.com and pick up the part after q= from the URL
Finally, the end result, you can see on the right side of my blog :)
Now all I have to do if to upload some new photos to if this really works...