Obviously, this method will have a number of limitations: you'll need an unlimited texting plan, for one. And, even if you do, you might experience delays and missing text messages if you're requesting particularly long pages, like Wiki entries. It certainly can't replicate the experience of a proper web browser, but as one of the developers told Fast Company, it's one "way for people to get information when they're in dire need of it." The browser's developers plan to release the app as soon as the end of September, but you can look at the project's codes right now over at GitHub. If you can't wait, though, you can try a similar, experimental app called Smozzy launched a few years ago, initially for T-Mobile subscribers.
Update (09/18/14): You can now get the latest updates on the Cosmo browser from its new website.