As a prominent iOS developer noted on Twitter, looks like Apple is actually toying with a standalone iTunes Radio app, as previously suspected.
In addition, Apple looks to be prepping new stock iOS 8 apps - TextEdit and Preview - as well as potentially enabling third-party Siri access.
Code hooks and hidden assets discovered in the iOS 8 Beta code seem to support these findings, largely corroborating much of the earlier findings by prominent Apple blogger Mark Gurman.
Note that this is no guarantee that Apple will roll out these features - that is, it will only introduce them when they're ready for prime time. For example, The New York Times previously reported that split-screen functionality didn't make the cut in iOS 8. With that in mind, it's fairly safe to speculate that Preview, TextEdit, third-party Siri access and a standalone iTunes Radio could be slated for the iOS 8.1 update...