Here's a comparison video that illustrates what we're talking about. What we've done here is to capture the Xbox 360 and the PC builds, both running at 1080p. The difference is obvious - the 360 is upscaling its 608p output up to 1080p. Indeed there are two scaling processes in effect: first up, the native resolution gets scaled to 720p, the HUD elements are added and then the Xenos GPU upscales everything again, this time to 1080p. The PC version operates differently of course, rendering the whole scene at the native resolution.
As our video player isn't happy processing a 1080p image, here are the 1080p captures from both machines cropped down on each side to give us a 720p image, but without any downscaling - one pixel in this video is one pixel on your display. As with the console vs. PC resolution comparison, we switch between each version and provide some head-to-head action too.
The Call of Duty games are all about providing a certain type of gameplay experience, and in the case of the console versions this is delivered through compromise. By and large the cut-back elements are handled skilfully and the games are still very satisfying to play, but the ability to power past the limitations of the console games transforms the quality of the game campaign. Even if you've completed it on console, it's a highly worthwhile experience to do so again on a high-power PC. You can't help but feel that this is the way the game should be played.
However, we're not kidding when we talk about a "high power PC", with respected benchmarking sites claiming that a 2.66GHz Core 2 Quad or AMD Phenom II X4 920 is required to get a decent performance level. In terms of graphics cards, our GTX480 is clearly overkill for the game, but anything from a Radeon HD 4890 or NVIDIA GTX 260 should give good performance on high quality settings up to 1680x1050. To sustain 60FPS at 1080p, a GTX 460 or Radeon HD 5850 looks to be the best bet.
Split-screen aside, the PC version of Black Ops does everything the console games do, but when it comes to the multiplayer side of things, it is fair to say that the game is enjoying mixed fortunes. The good news is that Infinity Ward's disastrous flirtation with P2P gaming on PC has rightfully been given the heave-ho - for COD purists, the option to run with dedicated servers is back. Treyarch has opened up the multiplayer side of things this time and the "you'll get what you're given" approach Infinity Ward took with Modern Warfare 2 is thankfully a thing of the past.
The bad news is that there's a sense that multiplayer performance wasn't effectively tested before the game shipped - dual and some quad core owners got a virtually unplayable experience on the launch day, and it took Treyarch a couple of days to patch some of the issues. For us, powering through the game on a Core i7 CPU, this wasn't really an issue, but it's genuinely surprising that the biggest game of the year should be effectively broken for much of the userbase on launch day.
Another element worth bearing in mind is that Black Ops on PC is built around Valve's Steam framework. You don't need to buy the game from Steam, but you will need the client installed in order to the run the game. On the plus side, this does mean that you get access to the Steam cloud system for syncing game saves and it also means that an Achievement system is in place that mirrors the 360 and PS3 accomplishments.
Multiplayer unpleasantness aside, the PC version of Call of Duty: Black Ops delivers what we really want - the ability to enjoy the game to its fullest extent without being held back by the technical constraints of five-year-old console technology. It may well be a "console port" as some of the more vocal members of the userbase are saying, but it's one of the few multi-platform games we've seen where the developer has rewarded the player for his investment in top-end gaming hardware with core assets that easily surpass the quality of the console equivalents, and the single-player campaign mode in particular benefits greatly from the upgrades.