You don't want to hardcode in the ruby_gem id here.  If you do, your "Reviews" link will always take you to the reviews page for the gem with ID 1 or will throw an error if there isn't a gem with ID 1 in your database.  Similarly, your "Review a Gem" link will go to the page to review gem w/ ID 1, or will throw an error.

I'd just omit these links altogether.