Forget about all those clever headlines about “hole-filler” filling its own funding hole. With no discernible business model, and very tough to serve ads against random uploaded pics, these Twitter-based picture sites do deserve to sink down the hole. But don’t let that hold VCs back from funding them. TweetPhoto, the San Diego-based online photo sharing service aimed at Twitter users, has received $2.6 million in its first round of funding, led by Canaan Partners, with additional investment from Anthem Venture Partners and angel investors. The money will be used for “development of its core offering, a platform of open APIs and mobile SDKs.” Yep, nothing about revenue. That’s because it won’t have any, nevermind that it is looking to expand beyond Twitter to Facebook, Foursquare and LinkedIn. Only saving grace: that’s true for every other similar photo service like Twitpic, Yfrog and others. That, and oh, a hope to be acquired by Twitter, to fill its own holes. Details in release.