Many eyes will be on Blizzard tonight as the World of Warcraft developer unveils the next expansion for its enormously popular MMORPG. Many miles east, id Software is expected to use its annual Quake Convention press conference to unveil its own next step.
Commercial success is as certain for both projects as the individual companies are renowned for their perfectionism. Both developers are expected to continue down paths already well-marked by their respective heritages. But there is less certainty in where id Software will choose to tread, and arguably more significance to the potential revelation.
The dilemma that will have preceded tonight's unveiling is nothing to do with the Texas-based developer's game engines. The company has been forced to reconsider its approach to technology recently, expanding its range of supported platforms and reducing its reliance on programming genius John Carmack - itself a very significant and many would say long overdue development - but it is in no danger of disappearing on account of any perceived sluggishness in this regard.
Harder to bear and harder to react to will have been the realisation that whereas the original Doom and Quake games were critical success stories that endured in gamers' affections for many years, its most recent internally developed title, Doom 3, found less acclaim, and enjoys less residual popularity.
The original Doom titles were subtle blends of amazing pace, frenzied action and straightforward puzzles, and it was their very abstraction that ensured their success. Theirs were worlds and physical rules that could only be realised in the extraordinary setting of a computer or video game.
The first Quake title took that approach and rocket-jumped with it. Its successors, Quake II and Quake 3 Arena, coupled the pace and the action elements of those first games to id's burgeoning prowess in networking and reaped similar rewards.
Doom 3, while superficially similar to past titles, rejected many of their fundamental strengths in favour of a slower-paced, brooding game of things that go bump in the night after an experiment that went wrong, and was accused of clawing for the coat-tails of Valve Software, whose competing Half-Life title - itself built upon id's Quake engine technology - had rewritten many of the genre's rules about storytelling, action sequences and pacing several years previously.
The result was perhaps inevitably id's least enduring title, despite strong launch reviews, and it was also one of its least influential.
Murmurs from the company ahead of tonight's anticipated unveiling have been of consistency but also change. How that manifests itself will be fascinating to observe. Will the company return to the comfort of abstraction, and seek to expand further into a sub-genre whose most recent successes include a little game called Gears of War?
What's more, its decision to collaborate with a British company, Splash Damage, to develop multiplayer title Enemy Territory: Quake Wars, may not preclude it from revisiting the competitive multiplayer action of a game like Quake 3 Arena. Will it return to that comfort?
Will it, instead, seek to show that it has learned the lessons of Doom 3, and boldly step back onto the most recently trodden path, the one that must - however little it talks about it - have given it comparatively severe discomfort?
Or will it deliver on its pre-conference hype and attempt to diversify, rearranging the fundamentals into some hitherto unexpected alternative?
Whatever the answer, tonight the company that originally took its name from the psychoanalytical term for the part of the psyche that gives birth to the innate desire for pleasure and satisfaction will be giving us an insight into how ego has weighed upon its creativity.
For an industry sometimes accused of cravenness and cynicism, the resolution of that internal debate will surely hold great and wide significance.