“The communities allow members to write product reviews, post comments on the reviews of others, participate in discussion boards and post ideas for the community to vote on. They can upload photos, and write blog posts as well as exchange private messages with other community members”
But why will they? What is the strong reason for them to take these actions? What is the motivation for a user to add a review? What do they get from it? "Getting advice before you buy" isn't strong enough. You can allow people to do a lot of things, but unless you give them a strong reason to do so, they probably wont do anything.
If you want people to write reviews of products, appeal to a strong motivation. Are you looking for the top product experts in each state? Are you launching an online shopping assistants club? Do people who submit helpful reviews gain loyalty card points? Is there a rare opportunity to become digital KMart advisor? Your appeal needs to speak to a person’s drive for fame, power or money etc…
And if you’re going to launch your community with phony reviews make sure that a) You include negative reviews and 2) The reviews are very different.