Tomorrow’s the big day, Android fans: we’ll finally be able to put months and months of rumor to rest, and begin months and months of arguing over whether the Samsung Galaxy S III or the HTC One X is top dog in the smartphone world. The Galaxy S III is, without exaggeration, the most rumored, leaked, faked and anticipated Android phone yet, so we figured we’d do a roundup of what we’re likely to see at Samsung’s London even tomorrow.

Form Factor: Basically identical to the Galaxy S II, only bigger. Numerous leaks point to a device similar in size and feel to the Galaxy Nexus.

Screen: Somewhere between 4.6 and 4.8 inches. This leaked screen protector, when compared to the 4.7-inch HTC One X, shows that it’s likely to be just a tiny bit bigger. There’s no doubt that it’ll be a Samsung-made 720p Super AMOLED panel, and probably a  non-Pentile Super AMOLED HD+ one at that.

Processor: Samsung itself has said that they’ll be using the brand new Exynos 4 Quad in “the next Galaxy”. That’s certainly the case for international models, but we’ve heard tell that at least some American versions will go with the popular Snapdragon S4 from Qualcomm instead. Today’s look into a Verizon user agent string seems to confirm that – perhaps the latest Exynos isn’t quite ready for LTE networks, or at least those in the US.

Operating system: Ice Cream Sandwich and the latest version of TouchWiz, without a doubt. One of the later leaks shows version 4.0.4 running, but it’s still possible that the final hardware will still be on 4.0.3 when it’s announced tomorrow.

Body: Like HTC, Samsung seems to be sticking with physical buttons despite Ice Cream Sandwich’s virtual nav button functionality. The same leak showed a layout similar to the previous Galaxy phones with a slimmer and more angular Home button. According to a retail listing, the phone will come in white and blue initially.

Camera: We’ve heard rumors that Samsung was going with a 12 megapixel rear camera on the Galaxy S III, and this AnTuTu benchmark listing seems to bear that out. Other leaks seem to indicate a more conventional 8MP sensor.

Connection: European versions of the Galaxy S III will almost certainly run with HSPA+ bands to start with – LTE simply isn’t widespread enough yet to justify the expansion. American versions for Verizon, AT&T and/or The Now Network will probably include LTE, as will at least one version in Samsung’s home territory of South Korea.

Carriers: Those of you in Europe or Asia probably won’t have to much to worry about – Samsung and other manufacturers tend to play nice with everybody, since unlocked models are so readily available. Here in the States it’s a different matter. While all four major carriers got a crack at the original Galaxy S, and only Verizon sat out for the Galaxy S II (for an early shot at the Galaxy Nexus) we’re not sure what the situation for the Galaxy S III is. Verizon seems to have the phone up its sleeve, or at least something very similar: the “SCH-I535″ was spotted earlier today in a user agent string.

Name: Now here’s one thing we’re not sure of. Continuing the Roman numeral scheme with “Galaxy S III” seems most likely, but we’ve seen Samsung’s official Kies program call the phone “Galaxy S3″ and a few other outlets label it as “Galaxy SIII” (no space). But who really cares – we’d be just as excited if they called it the Galaxy S Cauliflower.

There’s still a few things we’ll be looking out for at Samsung’s announcement; the more far fetched early rumors of a waterproof ceramic case are probably duds, but we want to know about battery capacity, MicroSD card options and storage capacity. And, of course, price. Join us tomorrow afternoon as we lie blog the Samsung Unpacked event from London – and place your bets now.