Yes if you make it different from the rest of them. When you come up with the ideal you should let me know. You will compete with Facebook which is like a burger shop competing with McDonald's worldwide.
There are several social networks out there that from day to day make new upgrades to ensure their websites remain outstanding. You will therefore find it challenging to launch your own social network unless you have a unique platform and designing that have need be used by any social network before. However as it is usually said that the elevator to success is always out of order and you have to use the staircases one step at a time it may never be too late to create one since also your colleague social networks like facebook, twitter, LinkedIn and YouTube started from zero have to where they are now.
If you were to start a social networking site these days, I think it should be approached as a business endeavor in and of itself, rather than a way to promote an existing site or business that you have.
As such, I think it would be best to approach it as a business venture with long-term growth in mind. For funding -- and I think it would definitely require funding to outsource some of the work and to generate publicity -- you might want to consider crowdfunding at sites such as Kickstarter and Indiegogo. That way, as you raise funds for the venture you could also attract followers. Plus there is the possibility of publicity when you use crowdfunding.
Think big, in other words, and plan accordingly. A social network these days I think would be a great ambition, and achievement if you can pull it off.
I really would like to create my own social networking site. However, it seems to be very difficult to launch. Most people don't really want to stray from what they have already, but the newest trend is always right around the corner. I think the best way to really make it happen would be to make sure it has a very eye catching and easy to navigate layout. I know that every so often, facebook changes their layout and makes it harder to navigate, I think a lot of people crave simplicity and those are the websites that seem to take off the best.
Depends on whether you are trying to take on the behemoths or if it is tailored to a specific niche. What can you offer that will be different? If you site grows to even tens of thousands of users, how will you be able to afford the infrastructure?
If you want to create your own social networking website, I say go ahead. There are people here saying it's not a good idea because of the competition from Facebook, LinkedIn, and Twitter—but who cares. You just have to work hard and try to think of something different from the other social media websites.
I say do it, there is always a way to do things differently. I wish I could have a social network based on my specific interest. It's had to network with people with your interest. My Facebook is full of people I know but they don't have much in common with me. Twitter is basically for marketing but its kind of hard to collaborate and share ideas.