Glad to hear RokuCo straightened themselves - 1099-K is the correct form to use for tax-year 2012 and later (per 2008 law, see
TurboTax write-up). And per
per IRS, "K" is to be furnished only for #transactions > 200 && grossReceipts > $20000 indeed.
Couple of years ago i was weirded out to hear the Co were sending 1099-MISC - because legalistically speaking, it's not RokuCo contracting developers to perform a service but the other way around, per contract "[Roku Inc will] perform the payment processing services corresponding to purchases of the Content [... and] retain a portion of the revenues received".
Note the use of different tax form does not imply change of tax situation. For sole proprietors (individuals) the income will still have to be reported on 1040 Schedule C form (regardless of the 1099 form type or if there is a form even), subject to business expenses and deductions. My personal understanding - not a professional tax preparer.