The Samsung Galaxy S II has built up a lot of hype, and while it’s not out in the United States yet, it’s been getting rave reviews overseas and from early birds here.

The latest buzz about the phone, Android Police reported, is that it’s getting rebranded with some wacky names when it hits shelves in America: the Within on Sprint, the Attain on AT&T and the Function on Verizon.

But what’s in those names? Here’s what people are saying:

Specs: The Galaxy S II has: a 4.3-inch AMOLED screen, an 8MP rear-facing camera that’s also a camcorder, a 2MP front-facing camera, a 1.2 GHz dual-core processor, 1GB of RAM, 16GB of internal memory, a microSD card slot and an NFC chip. The phone is going for about £500 ($826) right now in the UK for an unlocked version. Carriers will likely subsidize the phone when they officially announce it. Business Insider indicates that will likely be sometime in the third quarter of 2011.

Hardware:The super-slim phone stays light because of its plastic body, which felt a bit flimsy and cheap to some of the reviewers — belying its hefty price tag.

But the reviewers can’t say enough about the phone’s display, which Boy Genius Report’s Jonathan S. Geller called “one of the best screens I’ve ever seen.” The screen is supposed to display very sharp colors and save battery life by ditching the backlight and only displaying the pixels in use.

The front-facing camera is functional but not spectacular, reviewers said. The rear-facing camera, on the other hand, got very high marks, and Slashgear’s Chris Davies said it’s “capable of some very impressive, natural looking shots.” The Register’s reviewer, Dave Oliver, also liked the camera’s extra features, such as face recognition.

One feature mentioned in many reviews is the ability to silence the phone by simply turning it face-down on a table.

Software/Performance: “General responsiveness is absolutely exemplary,” said Engadget’s Vlad Savov. The preloaded video and photo editing software got middling reviews.

Samsung’s TouchWiz user interface overlay got mixed reactions from reviewers, many of whom like the standard Android UI or HTC Sense instead. In fact, TouchWiz’s lags and quirks seem to be the only things that hold the phone back.

“It’s an acquired taste, certainly, though has become somewhat more palatable over the course of its various iterations,” Davies said.

Bottom lines: The Register: “While the battery life isn't the greatest, its slim profile, powerful processor, 8Mp camera and (almost) all the latest treats Android has to offer, make it the top dog in its field.”

Slashgear: “Samsung has upped not only its game but the benchmark for smartphones in general.”

Engadget: “ ...if you're asking us what smartphone to buy today, unconstrained by such externalities, the Galaxy S II would be the clear choice. Sometimes it’s just as simple as that.”

Boy Genius Report: “Hands down, the Samsung Galaxy S II is the greatest Android smartphone available on the planet… if you can get past TouchWiz.”

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