
Well, you had that great idea. Everything set up and planed nicely so you could start to build that “thingy” to blow up the already crowded Web2.0 market. But, how do you check the chances of surviving? We’ve seen great products succeed or fail and the line between both scenarios is frightening thin.
I’ll present some well known examples of success and provide you with a hint to a possible root of their success. As always in the fast-living world of the web there are a lot more factors than what I could list here, but if I may pick just one thing from every application and abstract it to an advice, these would be the ones.
Offer a new service
Collaborative project management as complete and as streamlined like Basecamp was simply not around before 37Signals launched it back in 1999. And I’m not even talking about the pricing model here!

Efficiently streaming video over the internet and presenting it with a wide spread cross-plattform plugin – and this for mere mortals? Unthinkable before YouTube launched.
Offer a better service
Photo sharing was around for some time and it even worked for a broad audience, but now everybody can use a sophisticated photo-organizer online and share their pictures with ease thanks to Flickr.
Offer a simple solution
Google definitly wasn’t the first search-engine. But they knew the importance of simplicity when searching so they kept their Homepage minimized to the famous one-line search field.
Offer simplicity to complex processes

Easying the problems a lot of people are faced with is a shure shot in delivering services. The famous $ function from the prototype library has been one of the most duplicated functionalities.

Publishing on the net has become incredibly easy but setting up the publishing engine still wasn’t for everybody as easy as desired. With the WordPress-installation taking less than 5minutes they made it a snap.
Offer sophisticated tools

Del.icio.us isn’t the prettiest site around, period. But the functionality is undenyable and they offer a great set of tools to make using it even nicer. Posting links on the site itself fades to be secondary as illustrated by the position of the “post” link on the homepage.

Maintaining a personal tumblelog can be a time consuming process but with the superb toolset of tumblr.com posting content is just one click away. Appart of the bookmarklet they provide a great API and feed implementation.
Offer open data
What good are you’re statuses if they’re closed away on a site far away from your digital home? The portability of the data and openness of the Twitter API let developers easily integrate them anywhere. We can also see some complete new applications exists on top of Twitter. See Foamee for example.
Offer your plattform
With a global player offering his plattform for developers we see a nice example of a new direction in the portability of data.
Be remarkable
I still remeber the first time I saw the nice semi-transparent black in the background, the smooth transitions between the different images and the well-known preloader.. everything looked sleek and there was only one tought in my head: gotta have this! Visit the Lightbox 2.0 site
Be desirable
The digg-rank quickly became THE measurement for news-stories. What better situation for an app than beeing the referee for such a gigantic field known as the news.
Be the missing link
As we’re all customers, we all know the problem with hotlines, contact-fields, support-tickets and what-not. The chain between provider and customer is mostly broken. Here comes in GetSatisfaction.com, makes support go social and fills in the gap.

Your mention of digg reminded me of the flip side of being successful, crowdedness. (If it’s a social site, that is.) I liked the concept in the beginning, but nowadays I can’t read that site anymore… The same thing happened to YouTube and Facebook, they’ve been overtaken by the masses. Interestingly, I don’t have the feeling, that flickr is crowded, even though they too have many users. So, what is the magic ingredient that can make your site successful while still keeping it from being overhyped and overrun?