The best replacement for airtunes is airplay.

The best alternatives to airtunes are rated as following:
★★★★★  airplay
★★★  sonos
★★★  airfoil

Your alternative for airtunes is not listed? Suggest!
Speaking about airtunes, one probably shouldn't forget about airport extreme.

Other search terms related to airtunes and their ratings are:
★★★★★ airport extreme
★★★ airport express
★★★ pandora
★ express
★ front row
You have in mind a companion for airtunes and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of airtunes in all years. Click on graph for more.
airtunes
airplay
sonos