Second Life's fans love the complexity of this particular virtual world, where you can find anything from virtual offices to Seussland, recreations of 18th century Venice and London and contemporary shrines to 9/11. It's the richness, variety and practical utility of SL that keeps many people coming back.
Speaking personally, I go through cycles of fascination and disenchantment with SL: there are times when it seems to evolve too fast and mimic the real world too closely in terms of a lack of safety, there are times when I miss the promise it holds out and delivers on.
What most of us were expecting from Google Lively was SL on steroids: more complexity, more brilliance, more intensity. But that's not at all what Google had in mind. Google Lively is focused on being user-friendly. Instead of a complex choice of avatars, the first-time user gets a few basic options.
Instead of a long registration and download process, you can log on to Lively in a matter of minutes. Instead of a virtual world, what you have is distinct virtual rooms, from Jen's coffeehouse to a Lost World replica to a space for Trekkies.
Initially, the Lively experience is disappointing. Many of the rooms are empty in this early beta stage. The environments are less immersive than SL or other virtual worlds. Though it's easy to build rooms, you can't at this stage import objects easily - so you're stuck with the furniture and background options Google currently offers.
But here's the thing. Once in a while, I've invited a non-geek to drop by SL. For many people, just the process of getting used to SL - the infamous first-hour experience - is so tedious, complex and bewildering that they never get past the initial barrier.
Google Lively's lack of complexity is actually a virtue for those who have never been exposed to the virtual world phenomenon. It's easy to jump in to a Lively room and get started; the glitches can be overcome even if you don't have much technical skill.
Though I missed the rewards that a fully-fledged, connected and constantly evolving virtual world can offer, I had to concede that Lively's single-room structure might give it a significant edge in the future. Think of the difference between constructing a vast stadium, and between constructing a series of tents that can be dismantled, shifted or reconstructed with ease.
Rooms from Google Lively can be linked to, much like YouTube videos, on Facebook pages, websites, blogs et cetera. What SL and other worlds of its kind offer is something like the Matrix: a sprawling world that exists almost in parallel to the Internet, and that requires time and skill to negotiate.
From the corporate perspective, for instance, an office in SL needs to be secured from possible threats by outsiders, much like an office in the real world. But once you have the option of restricting users, it's easier to build and protect an office "room" in Lively.
As it progresses, Lively is sure to acquire layers of complexity - and at that stage, it will offer an intriguing challenge to the current model of the virtual universe.