"As opposed to Google’s tool, at Cover Tagger you’ll not only score points for real-time matches with others, but when your keywords have been answered by others at any time"

I believe that's not entirely true. I mean in Google Labeler you not always play real-time matches with others, it also uses sets of keywords that have been given by others at any time...
As you probably know Google Labeler is a copy of ESP Game. Now look at this part of the lecture for Googlers by creator of ESP Game:

http://video.google.com/videoplay?docid=-8246463980976635143#15m33s

He says:

"There's also a single player version of the game. It's important to have a single player version of the game for several reasons. One of them is the number of people playing the game is not always even. But also, whenever a player drops it's important to just basically have them keep on playing the single version of the game. And how do you get a single player game? Well, you simply can pair up a single person with a prerecorded set of moves. The idea is as follows. Whenever you have two people playing you record everything they do and when they do it. So you record all the words they enter along with timing information. And whenever we're going to have a single player play, we simply pair them up with their prerecorded set of moves. So the single player is playing with somebody else, just not at the same time.

One nice thing about this, notice, this actually doesn't stop the labeling process. That single player is playing with somebody else, just not at the same time; so everything that I sad about labeling remains true. In fact, we could even go one step further; we could do the zero player game. We can also pair up prerecorded games with each other to get more labels."

Not sure, but the Google Image Labeler's help says

<<Who will I be paired with?

You'll be paired randomly with another Google user who's online and using the feature.>>
http://images.google.com/imagelabeler/help.html

I dont think so, I think its not as same as Image Labeller

Would be nice if you made this a bit more social and FUN, things like highest scores, overall scores, positions on a ladder. Rather than treating us like human fodder for the machine- something that Google does with any of its projects that fail miserably on the social count eg compare the fun factor in esp game vs image labeller.

At least you images are nice and big anyway :) ..and the covers are cool to look at.

I was hoping the fun in this game comes from looking at covers. In a way, it's a "random cover" gallery, but I wanted to have more than just a random cover feature. But it's definitely the big challenge here... how do you make it as much fun as possible? And how do you make it more social (preferably without asking users to register, which I always try to avoid if possible)? For example, I thought about adding little prizes – in the form of special images? – if you score high points. Any ideas on this are welcome.