Granted, Opera's not the first company to try this. They're not even the first Scandinavians to do it: I wrote a while back about Nokia's Mobile Web Server, which does something very similar using a dynamic DNS service and ports of Apache and Python to S60. It's kind of funny, actually: even when I wrote that post, I thought a lot of the applications I proposed--data collection apps, location-aware multimedia blogs, peer-to-peer REST APIs--might be a little far-fetched. Now you could practically drop my post into Opera's Unite pitch without changing anything other than the brand names. It'd blend right in.
Given my interest in digital activism, the first thing that came to mind was the usefulness of this technology for dissidents. Sadly, Unite suffers from the same problems as most Web 2.0 communication technologies: its idea of decentralization, isn't. In repressive environments, that makes it potentially vulnerable.
Opera claims that Unite is decentralized--and it is, to a certain degree. In theory it moves user data away from repositories like Facebook and Flickr, and leaves them on your individual machine. But in reality, Unite simply moves the centralization into the network channel itself. Despite the claim of creating an "interpersonal web," the service doesn't actually connect users to each other directly. Instead, to handle the problem of addressing dynamic servers, as well as providing some degree of security, all Unite traffic goes through Opera's proxy servers and is routed to its actual destination.
Having a proxy server, of course, is not a bad idea. For activists it might even make a lot of sense: it adds a layer of obfuscation, and means that the data server can't immediately be physically located via its IP address. And Opera has a lot of experience in proxy technology: its Java-based Opera Mini browser provides a fantastic web experience on resource-constrained devices by running page requests through a proxy that compresses them. I don't use it for anything secure, but it's astonishing how much faster it is for basic reading compared to a full Webkit mobile client. Opera probably also has a way to monetize the Unite accounts required to use its service, and which serve as the subdomains for users.
In a repressive environment, however, this strategy is disastrous. Take China, for example: you may have heard that a few weeks ago, on the anniversary of the Tiananmen protests, China simply shut down Twitter, Facebook, YouTube, Flickr, and a number of other social networking tools. For all its talk of decentralization, Opera Unite could be shut down just as easily, simply by blocking access to unite.opera.com. Suddenly that "interpersonal" web collapses. Likewise, if anything goes wrong--or if Opera caved to governmental demands--any traffic moving between Unite servers through their proxy would be vulnerable. So much for security.
Granted, not every regime is as competent--or as concerned--as China when it comes to ICT. We're all aware of how Twitter (among others) has become a part of communication in and out of Iran. Why hasn't it been shut down? As Evgeny Morozov argues, it may simply be a matter of priorities: when you've got real riots in the streets, riots on a microblog service probably seem relatively inconsequential--probably are relatively inconsequential, being more useful for publicizing protests than for actually organizing them. My cynical side also notes that (if they've thought about it this far) Iranian authorities may see an advantage in allowing the rest of the world to see this as a dramatic electoral struggle, rather than merely a dispute between two Shah-chosen figureheads--but then I know nothing about Iran, and you should certainly take my opinion with a ton of salt.
Despite my doubts, I think a Unite-ish system could be very useful for activists if combined with a user-run proxy system. It makes information dissemination flexible, simple, and mobile: as easy as sitting down near a wireless hotspot and opening up a browser. Adding some kind of discovery mechanism for the proxy--maybe via a distributed, browser-based darknet--or a process for spamming its location to blogs/e-mail/messaging when online would make this a powerful way for activists to share their data without giving up ownership to a third party. There's no reason Opera themselves couldn't lead the way on this, based on what they've done with Unite so far--but it looks unlikely.