This is a Toy Fair photo (which fair is unknown) but they were previewing this set of unusual Boom plush dolls. They're rather silly, in the 'chibi' style (little-big-heads) with micro bodies & limbs, with big faces/heads. The quality here looks good, for the most part. Tails reveals that the eyes are embroidery (always a good touch) and each character seems to have 3D accessories like the goggles (Tails & Eggman) & scarf. Poor Knuckles looks like his nose is a bit pushed in/very tiny but silly angry Eggman is fun. Release date & price point for the dolls is unknown in spring 2015, will be added.

At the right is a fan photo for the release of little-big-head (chibi) Boom Sonic. He's just above, in the toy show display, but when actually released, the cardboard display box only contains Sonic plushes. It looks good here, about like the factory photo, with all the details in place. The ear borders are a bit slim, but it otherwise looks cute/silly and Boom-accurate enough. You can see the square paper tag hung from the ear, with Sonic leaping over the Boom logo.
Despite their not-that-large size, these dolls are around 15.00 , and only sold at Toys R Us. 

Photo by CrystalSonicFanAnd now, little-big-head Knuckles appears in stores. The Sonic (above) was released first, hopefully Knuckles showing up means the other 2 characters are on their way. Here, you can see him along with the Sonic & their regular-proportions boom-Sonic plush, so you can compare the sizes. They're soft, and full of light-weight material. They've kept all the details though (it looks like) with the lines on his shoes, and stripes on his gloves for the bandages. The head looks decent, perhaps a bit more proportional than Sonic's, since he doesn't have such a huge lower face. With the TRU tag there, you can see they're calling them "Sonic Head Plush". 

Photo by Taaron

Here's little big head Tails, as a factory photo / official photo.
He looks about like the Toyfair item above, which indicates consistency in the product, but, much like the Sonic, he suffers a bit from 'giant lower face'. He's still fairly cute, but the larger lower face area adds a bit of an ape-like quality. The goggles are 3D/stuffed, and his belt/strap is colored on (not an accessory) The lines for his fingers & shoe bandages are also printed onto the fabric. Notice how he has ear-edges that work well, unlike the Sonic from this set. Despite their not-that-large size, these dolls are around 15.00 , and only sold at Toys R Us.

Here's line 2 of the Little Big Heads Plush!
Line 2 has new characters Orbot & Cubot, plus another Sonic to choose from, then adds Sticks & Shadow. What's the Metal Sonic there? He's clearly smaller...is he from another plush line?

These look pretty much like the prototype photos, and the head shapes appear to be holding up well. They're here in the display box which looks the same as the original. The right photo shows the real little bighead Metal Sonic & gives a better look at the Shadow & Sonic's expression. Sonic looks aggrivated, and Tomy continues to leave out the ear borders for everyone except Sticks. The right photo is at NY Toyfair by I09, The left photo is at the Germany Toy Fair (note the strip in the background) 

 Here's a better look at Amy & Shadow from the 2nd wave of Little Bigheads Boom plushes. The heads look pretty nice for both characters, though they're still forgetting the ear borders & just making them 2-sided cones (which does not match the show) The other details though, they're attending to, such as Amy's eyelash line & Shadow's red eye-border being quite appropriately sized & embroidered.

Amy's bangs look good, & her spikes seem proportional/thick enough. Shadow's head shape seems decent & his stripes appropriately placed. The bodies are...well...little, due to the style of the dolls. Amy's dress just makes her look like a cube because it covers her near-nonexistant legs. Do note that the white patch for Shadow's chest is still there. These look like cute enough editions if you like this little big head doll style. (Though the backs remain to be seen) 

Photo discovered by PatMac