According to The NPD Group’s Retail Tracking Service, Bluetooth headphone revenue overtook non-Bluetooth for the first time in June accounting for 54 percent of headphone dollar sales and 17 percent of unit sales in the U.S.
And:
Beats and LG have led the Bluetooth headphone market throughout the first half of the year, accounting for approximately 65 percent of dollar sales.
Not necessarily a direct indication of decline in wired headphones, but a sign that, as average prices of Bluetooth headphones go down, consumers may prefer wireless.
Removing the headphone jack from the next iPhone will be annoying; at the same time, limitations notwithstanding, I can’t deny how nice it is not to deal with wires anymore.