To check whether your podcast cover art's URL supports HTTP HEAD requests, enter the image's URL into, and switch request type to “HEAD.” If it works, then the server supports HTTP HEAD requests. LibSyn and Blubrry support HTTP HEAD requests. That means you can be in the iTunes podcast directory with small artwork, but you just won't have a chance at being featured. The most important takeaway is that Apple won't feature podcasts with smaller cover art. Apple has said that featured podcasts needed cover art at 1,400 × 1,400 since May 18, 2012. The image URL must end in “.jpg”, “.jpeg” or “.png” and the server hosting the image must allow HTTP HEAD requests. To be eligible for featuring on iTunes Store, a podcast must have 1400 x 1400 pixel cover art in JPG or PNG format using RGB color space.
ITunes has been completely redesigned and there are new requirements for podcast cover art. I'll explain this for you and tell you how you can change your podcast cover art or add some if you don't already have it. The language is very specific for easily misunderstood. Apple recently emailed podcasters to remind them (again) about the requirements for being featured in iTunes.
