So here is the BICEP2 picture:
How big is that? How much of the sky?
Say, compared to this picture of the CMB by Planck:
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The BICEP2 pre-print article says "effective area of 380 square degrees", which is less than the value you would obtain by just multiplying the sides of the rectangle in the plot above, since these are spherical coordinates. Also, in the article more-full versions of the plot above are shown; that above is a truncated version. http://bicepkeck.org/b2_respap_arxiv_v1.pdf
Planck is the full sky, about 41000 square degrees.