in regards to the varied distribution of attention in Showcase I threads, here are a number of reasons i can think of:
-- screenshots attract attention. screenshots that show evidence of effort and the potential for a brighter future with a few mistakes will receive more comments and criticism than average looking screenshots where there's nothing glaringly wrong for people to pounce on.
-- potential. something that looks like it will be playable/usable in the near future will attract a lot of attention if it's something people want to play. i'm not going to take the time to comment on something that i don't even want to play unless i need to praise that person for something that really impresses me.
-- youtube. or other video-hosting/playing sites. it's a lot less of a hassle to stream a video in the browser than to download and play a video in media player. if a link ends in ".avi" or ".wma" or something, i'm not going to click on it (unless it is a big update to Kiyaku's Angela's World or something). i'm more likely to click on a ".mov" or youtube link because that will play in my browser.
-- the user. if someone is pretty new to the forum and doesn't make it obvious in the first post that what they're doing is more than just an ambitious noob's dream, it's less likely to merit a response from me. noob's need to be encouraged, of course, to get out of the 'noob' stage, but when times are busy i'm not going to bother trying to set them straight and figure out whether or not they're worth paying attention to atm.
-- game. i'm more likely to comment on a game than anything else. i see model packs, texture packs, and examples of freelance artwork, but i'm never going to use any of them, and they are of no interest to me unless they are exceptional (such as Andvari's work which should be an inspiration to any aspiring game artist), in which case i will comment and say "that's good!". having said that, i enjoy having a look at aztec's frequent contributions because i can see how much he's improved over the past many months and he's actually producing some nice stuff -- yet i still don't comment on them, because i know there are many others who will reliably point out where improvements can be made, and they don't hugely impress me (as i'm sure aztec can understand at this stage). a game that looks like it will get somewhere is exciting, because we could really use some more sold games to show A6/A7's capabilities, or at least spread the word about it.

that's basically how i put my personal response to Showcase I threads into words.

what makes a game a game?

control. if the player can control what goes on, it's a game. i wouldn't call a "choose-your-own-adventure; pick option A or B" a game. that's more of an "interactive story". what makes a game a game is entirely dependent on how it plays, if the question is to be taken strictly.

it's a fairly ambiguous question, really. i don't have much more to say for now because i've spent too much time responding to this thread and admittedly my response is somewhat tangential, focusing on the quote from TSG_Torsten.

what makes a game a good game lies foremost in its design. a good game is (usually) designed well first, and then if the programmers, artists, and testers are worthy of their profession, they'll flesh it out as the designer(s) planned. modifications to the design are made along the way, but it's the design that makes the game good or bad.

uh... yeh... my two cents of rambling. maybe i put some subjective things across as "fact", but that's how good essays are meant to be done so i shouldn't let myself fall out of that habit until mid-next month. before responding directly to me, keep in mind that the whole "Showcase I" bit is an example of how i function, and by no means am i saying "this is how everyone works".

julz