The tag “best…game…ever” is frequently plastered on Deus Ex: The Conspiracy with justifiably fervent ardor, so to say that expectations are high for Deus Ex: Invisible War is just a wee bit of an understatement. Like the first game, Invisible War is a model of excellent game design, mixing a vast, gripping story with truly open-ended gameplay.
Some unfortunate technical issues crop up. The frame rate is sluggish at times, and while it’s not a serious problem, it definitely sucks. The load times between areas are long and frequent, too, and it really feels like the game needed another month or two of polishing.
Hardcore fans who idolize the first Deus Ex will also discover their share of disappointments. The compression of skills and augs into biomods robs the game of some of its rich depth, and combat is a more primary focus of the gameplay. The web of consequences for your actions and decisions also seems less complex and less compelling. Perhaps it was an attempt at more mass-market appeal, but the result is that the game is a bit too oversimplified and doesn’t reach the same lofty, godlike heights of the original. That said, it’s still vastly better than 99.9% of the other games out there today, and with properly calibrated expectations, you’ll find that Invisible War is a brilliant game that will captivate you like few others can.

Sure, some people will say that the game's made too many concessions to convenience -- no more skills and one kind of ammo spring to mind -- but all this means is that you have fewer concerns distracting you from the main point of the game, your experience making decisions within the game's story.

Pros: Cons:
Incredibly open-ended story Framerate suffers and middling animations
Highly realistic lighting engine Short playtime, even with multiple paths
Great tactical gameplay

Deus Ex let you go pretty far in throwing objects around, and that's still a big part of the sequel. Much press has been given to the improved physics engine governing all those broken vases, but it's still got a ways to go. While everything bounces around nicely, behaving according to the object's shape, there's not enough sense of weight to any given object. Bodies, barrels and bottles all look like they weigh the same as they fly through the air. Like other visual aspects of the game, the physics system is fine, but certainly not trendsetting.
While the visuals are definitely striking, the sound component in Invisible War is less so. There's a lot of voice acting, but most of it barely makes it to convincing, and the very similar voices that drive most of the NPCs rob the game of impact. The sound effects range from good, like a lot of the general ambience, to more run of the mill, and some of the constant bot voices get old after a while.

My fists decide the course of my character's life, not my tongue. In stark contrast to BioWare's Knights of the Old Republic (the most recent title of note to feature choice as a pivotal gameplay mechanic), nearly 90% of Invisible War is decided through action, not conversation. For most of the game, the shoot, bypass, or do nothing decisions feel quite liberating. They break the confining, established mechanics set by a few decades of entirely linear games. But in other ways, choice through action can be very constricting.
There are blatant and often times aggravating gaps between action and dialogue that a few more branching conversations would have immediately remedied. For instance (early on so that to be spoiler free), I killed a man after inadvertently falling through one of the ten thousand ventilation shafts that spiral in and out of Invisible War's world. Me, a female character named Abobo the Mighty, plummeted into his living room. He was quicker to shoot than question. Naturally and without a moment's hesitation, I dispatched him and then later, in an entirely different location I had yet to visit, found a somewhat unscrupulous proprietor of a not so happening nightclub soliciting this corpses' murder. Since he was already dead and I was stupid enough to try and speak with someone I had never met before, I immediately divulged the details of his grisly demise by sword and was promptly rewarded. What the heck? Offer me the choice to confess. Maybe I don't want this persons' money. Maybe I didn't want the outcome that killing that other man would entail. Maybe I didn't even mean to kill anyone to begin with. It was an accident caused by my admittedly sloppy navigation of ventilation shaft #346 and his inherently poor level of artificial intelligence. So, please give me the option of denial, the option to lie.
The end result is a good-if-you're-into-it, poorly performing, but interesting social experiment that seems more geared toward determining how players will react to certain situations than challenging them in new and exciting ways to accomplish tasks that are fun and engaging.