Well, okay then. Having issued the obvious warning, here's my two cents (which are not to be confused with scientific data or anything -- remember: test, test, test):

-- The home page is too wordy. Go look at Flickr's homepage. Count the words.

The reason not to be wordy isn't just that it's quicker to read, it's trendy design, etc. It's to avoid looking like a brochure. Your site right now reeks of "I'm desperate to sell something" and not of "We've got lots of nice pictures to share with you; come share some of your own". If I visited your site I'd probably click away before I read more than three words -- I'd see it was about photo sharing, I'd think "Flickr clone, by someone who writes brochures!" and off I'd go.

-- Put some content front and center. Design a fairly large widget that displays content in a way that emphasizes the special OurDoings[tm] format -- e.g. with the date and caption at the top or the bottom, or superimposed, and the photos fading one into another, or displayed as a gallery, or sliding right to left slowly...

The reason you need a special widget is that you want to show the content without making the user scroll the home page. You also need to make a clear distinction between a user's home page and the site's home page, and you want to be able to showcase a selection of different users on the home page.

Then write code that takes some of your users' most recently uploaded public content and puts it in the frontpage widget. Make sure that, if an interesting photo pops up, the viewer can click a big obvious link to go to the user's home page and see their "doings" in all their glory.

-- Include a list of links to recently updated home pages on the site home page.

-- All this content display will serve to highlight the fact that your content is both sparse and old, old, old -- the most obvious content, the demo, is from 2005! You can't create customers out of thin air, but you can get more out of the ones you already have -- particularly yourself. Get out there and take some pictures. Take pictures night and day. Make your friends take pictures. Put 'em up in public OurDoings pages. Make those pages easy to find from the home page.

-- So, suppose I've yielded to their superior marketing and created a Flickr photostream. Can I sign up for OurDoings, press one button, and get your software to suck down my existing Flickr photos and rearrange them into your nifty format? Flickr photos have timestamps, right?

If this feature already exists, it's a crime that I don't know it at a glance. Put a huge link marked "TELL A STORY WITH YOUR FLICKR PHOTOS" on your home page, because that's a great way for folks to test-drive your site. The thing about my Flickr set is that it's already on the Web, and I already know that it's got nothing except what I'm willing to share in public, so I don't have to do any work, or have any particular trust in OurDoings, in order to let the site play with my existing Flickr photos.

UPDATE: Hey, wait a minute. If you had a Flickr-processing feature, could I pipe all of the Flickr photos which were tagged "xkcd meetup boston" into an OurDoings album, click on the ones I want to keep, and rearrange them into a story with captions written by me? Suddenly OurDoings becomes an online widget for building stories out of multiple people's Flickr photos...

Obviously you've got to be clever with the design of such a thing to prevent griefers from DDOSing you to death. Flickr feeds can potentially feed a lot of photos...