The Samsung Infuse 4G, with a radio capable of achieving peak rates of 21Mbps, is being marketed as the fastest smartphone currently available from AT&T. It’s the big brother to the Samsung Captivate, and fits just between that device and Samsung’s Galaxy S II when it comes to hardware specs. The Infuse 4G packs a gorgeous and massive 4.5-inch display, a thin and light form factor, and a solid camera. AT&T’s first HSPA+ “4G” phones fell flat when it came to data — neither the HTC Inspire 4G nor the Motorola ATRIX 4G could hold a candle to the 3G download speeds available on the iPhone 4, and we won’t even discuss the upload speeds. Is the Infuse the AT&T 4G smartphone you’ve been waiting for? I’ve been trekking along with it for more than a week and have penned my impressions, so check out the gallery below and then hit the jump for my full review.