throttled so as not to overload the cloud-based components of the app. RockMelt will be doling out download links as quickly as it can manage on a first-come, first-served basis.

The two founders, CEO Eric Vishria and CTO Tim Howes, demonstrated RockMelt to Wired a few days before Sunday’s launch.

It’s based on Chromium, so it inherits Google Chrome’s speed, looks, and basic functionality on both Mac and Windows.

And while its Facebook integration runs deep, RockMelt is not exactly a Facebook browser. It’s a social web browser, allowing you to post links, videos and status updates to both Facebook and Twitter (that’s it for now, but more services will be added later). There are also built-in clients for consuming your Facebook feed and managing multiple Twitter feeds, a chat client, and lightweight RSS reader. It does use your Facebook account to personalize the experience, but its reach is broader than just Facebook.

We’ve seen browsers custom-built for the social web before, most notably Flock, which launched as a MySpaced-up version of Firefox. Mozilla experimented with Ubiquity, an in-browser tool for posting to different social sites and interacting with web services. There are a number of add-ons that can embed social networking dashboards into the browser for you. These tools have grown in popularity as we’ve struggled to manage the ever-increasing flow of links, media and bits shared by our online friends.

So, the idea isn’t original. And RockMelt doesn’t sport a complete re-invention of the browser interface, either. But it is very streamlined, and there are some key elements that people who live and breathe the social web will find intriguing.

First of all, you log in to RockMelt before you use it. You authorize the browser to connect to your Facebook account, and the browser is instantly customized for your social circle, showing your friends and your favorite sites in slim sidebars — or “edges,” to use the RockMelt parlance.

The edge on the left has your picture at the top, and the friends you interact with the most appear in a list below you. To send a new tweet or to update your Facebook status, you click on your picture. To send your friend a message or start a new chat with them, click on their photo. You can also share things by grabbing an image or video on the web page and dragging it on top of your friend’s icon.

The edge on the right has small icons for each of the services RockMelt tracks for you (only Facebook and Twitter for now) as well as spaces to add RSS feeds from your favorite sites.

The “edges” aren’t intrusive — they are less than 50 pixels wide each — but they do add extra visual heft.

“You can’t forget you’re a browser, and you can’t get in people’s way,” says RockMelt CEO Eric Vishra. “We designed these edges to be very thin, to be there when you want, and to blend in when you don’t.” You can also dismiss them with hot keys.

Clicking on one of the icons in the right edge — either Twitter, Facebook or a website icon — brings up a little pane that shows recent posts and activities from that source. Following the “keep things out of the way” philosophy, these panels can pop out from the browser to float freely if you want.

All of your user data is stored in the cloud by RockMelt (on Amazon servers) and synced when you log in, so no matter whose copy of RockMelt you’re using, you see your own custom version of the browser. Others are moving in this direction, too — Chrome connects to your Google account and Firefox has an agnostic Account Manager. But RockMelt’s Facebook integration is central to the experience.

RockMelt is polling Facebook, Twitter and your favorite sites periodically to check for updates (There’s no Firehose or PubSubHubbub magic yet, the founders tell us). But the feeds are real-timey enough. Updates show up in under a minute, often less. The updates are collected by the cloud service and pushed down to the browser.

There’s also a big “Share” button at the top of the browser. Clicking this button opens up an all-purpose sharing window, so you can tweet a link, post something to your Facebook wall or send the link as a message to a friend. Not a huge innovation, as we’ve seen something similar in Flock, but it’s nice.

Lastly, when you use the web search box in the browser, you get another floating window pane that shows the top ten search results. You can click (or navigate with keys) through this list, and the results flip by in the main browser window. RockMelt starts pre-fetching and rendering each one of those ten search results as soon as they show up (with Flash blocked). When you click through the list, you’re seeing real web pages, not snapshots, and you don’t have to wait for the individual pages to load. It’s wicked fast, like flipping through a stack of cards. It sounds bandwidth hoggish, but the browser calculates how much pre-fetching your connection can handle and adjusts accordingly.

Those are the big features. But let’s consider for a moment the elephant in the room: RockMelt is very, very Facebooky. It uses Facebook to sign you in, the in-browser chat experience is built on Facebook Chat, and when you share something via a message, you’re sending them a Facebook mail.

The founders say there are investigating other login experiences, like Twitter sign-in or OpenID logins using Google, Yahoo or AOL accounts.

“We’re going to remain agnostic and pick the services that the most people want to use,” Vishra says, but the team decided to “go deep” on Facebook simply because of the site’s size and volume.

Although it’s disappointing to see that the browser doesn’t play as well on the open web as it does on Facebook’s web, the tight focus makes sense for a young browser trying to gain a foothold in the mass market: Go drop your line where the fish are biting.

The downside being, of course, that if you’re not a Facebook person, RockMelt isn’t as interesting. I could see it being useful for Twitter power users who have a Facebook account, even if they don’t use Facebook heavily. But if that’s your angle, RockMelt’s chat and messaging features, which are based entirely on Facebook, are nothing more than food coloring.

This article originally appeared on Webmonkey.com, Wired’s site for all things web development, browsers, and web apps. Follow Webmonkey on Twitter.

More from Webmonkey:

• New Flock Is Simpler, Now Based on Chrome
• Mozilla Gets It Right, Moves Identity Management Into Firefox
• New ‘OpenID Connect’ Proposal Could Solve Many of the Social Web’s Woes

Authors: Michael Calore

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