Citysearch and Urbanspoon, both review sites under the IAC umbrella, have added new Twitter integration to their sites. For Citysearch in particular, the Twitter integration introduces a new option from Twitter’s API offerings, including a sign-up feature for new users. Those on Citysearch that wish to claim and manage their business’ content can sign up for Twitter directly on Citysearch.

This particular Twitter integration comes as a new offering from the microblogging company, enabling third parties to allow their users to register for a Twitter account through their site. Separate from Twitter’s OAuth offering, the new API option will likely be of great interest to third party sites and publishers. What the new offering does is make it even easier for people to create a new Twitter account, vastly expanding the potential reach of Twitter as a user base.

The benefit for Citysearch and Urbanspoon is the ability to incorporate community-driven, real time data. Businesses that claim their profiles on the Citysearch review site can also tweet from that profile, after having added or created a new account. Citysearch has also added Facebook Connect, combining the efforts of two major social media platforms. This allows Citysearch to centralize a business’ social media marketing, as you can manage and access your content and interactions across Twitter and Facebook.

From a centralizing perspective, Twitter is continuing to position itself as a profiling tool for users. As a microblogging tool, Twitter collects a great deal of information on individual users, slowly building up a profile of those users. While the ability to aggregate and redistribute users’ content, Twitter has the ability to collect a great deal of information on these users. Other sites can take advantage of the profile built up at Twitter and accessed for their own purposes. The appeal to users is in the convince this provides when creating new accounts.

It could be this potential data that companies like Citysearch use to incorporate into their own social media services. The necessity for other businesses to access and leverage this information makes for great monetization options for Twitter. The company has been preparing the public for a monetization strategy for some time, and the business-to-business capacity would surely introduce a valid way for Twitter’s business plan to arrive.

What this means for Twitter is that it is moving closer to becoming a business tool, generating its own stream of revenue. The expectations around Twitter as a business tool are rather high, given businesses’ interest in Twitter for their own marketing purposes. As such, Twitter will need to continue to build out its feature sets and maintain loyalties to its user base in order to see great success on this avenue. Attempting good relationships with users and protecting their interests is a central principle for Facebook, and could be the ultimate trump card for any impending competition between Facebook and Twitter.