It's not inconcievable that the reason they have yet to announce anything is because they don't have anything to show, mind you, I'm not saying that they're not working on the game, I could certainly believe that they are, and I do HOPE that they are. We must remember here that after Oblivion, Bethesda also developed Fallout 3, so it's not like Bethesda hasn't developed any new games since Oblivion, so it's not necessarily unreasonable that we have not heard anything new about any new Elder Scrolls games. Still, I hope we hear something soon, if the utter absence of news keeps going on like this, people might start losing interest, maybe I'll stop coming here regularly if this continues (though for now New Vegas probably gives me a reason to come keep coming back, and since I'm currently playing Morrowind I still check the Morrowind mod board to see if there are any new mods of interest occassionally.) though I'll still drop in on ocassion to see if there's any news of an Elder Scrolls V, I think. And while I can wait, that doesn't mean I want to.
I'm sure that once the next game is announced though, even if there's no information on it other than the fact that it will exist and the title, this place will gain a lot of new life, likely there will very quickly be increased activities in both the realm of suggestions and speculations.
There seems to be a sense of entitlement floating around. There is no law that says they have to please the fans, no law that says the can't publish games, no law that says they have to release news of TES5. Bethesda doesn't owe you anything.
Of course there's no law that says they have to please the fans, however, there's also no law saying that anyone needs to give them money if they don't make the games they want. I for one don't give a rat's behind about any of the games currently in development that Bethesda is publishing except for New Vegas. If Bethesda wants to publish games unrelated to Fallout or the Elder Scrolls, that's fine with me, but that doesn't mean I'll automatically care about the games simply because they have Bethesda's name on them. I'm already interested in Fallout and the Elder Scrolls, but to get me interested in the other titles Bethesda is publishing, there needs to be something to give me a reason to pay attention.
And Bethesda still does need to make money, while I'm not saying they're not making money now, I know there are people who would be willing to pay money for another Elder Scrolls game, seeing as I'm one of them.
Maybe Bethesda just have a really sadistic sense of humour and have already developed tesV but are just holding it back, so if we just quieten down about it they'll release the game.
I don't think that developing games, then not releasing them even once they're ready just to toy with fans is a wise business decision, seeing as Bethesda can't actually start making money from the game they invested in until copies of it start being sold, and besides, developers usually like to announce their games BEFORE they're released, and show screenshots, trailers and reveal various pieces of information about the game in order to generate hype.