is wordpress good for building photo community web site

I'm sorry, but there really isn't one answer. Can WordPress do this? Well, yes it can. There are a lot of social networking type plugins out there, the most popular of which is BuddyPress which is free and open source, and also has a lot of add-ons and such floating around in the form of plugins.

You could use BuddyPress and a type of gallery addon plugin to achieve what you're looking for. Now the issue becomes if what you want is fully achievable with just whats already available. If the answer is no, then you can still use the WP-BP combo, but you will have to write up a plugin or add code to either a site functions plugin or, (and i don't suggest this) add code to your theme's functions.php. If you cant do this yourself, then you'll have to bring on a developer to help you out.

Now, that is the nice thing about WordPress is simply the fact that you can make it do just about anything with a bit of custom coding. So you can definitely achieve your goal for a photo sharing website with WordPress.

The next question you have to get an answer to is what kind of hosting will be available to you? One thing that can easily deter users from a community/social networking website is slow response time. Especially if you want users to be able to upload media. While it is very possible to use all kinds of strategies to keep WordPress lean, there are still many areas of bloat that you cant escape. This isnt really a huge issue unless you're hosting plan doesn't give you the resources you need to keep things nice and speedy.

So if you're hosting plan isnt good enough for that, then you might want to look into other solutions you can built from the ground up as oppose to a big CMS. However, no matter you're solution the type of hosting you use will play a big part in it.

tl;dr Yes, WordPress can certainly do what you are asking, but whether or not this is your best option is highly circumstantial.