See here:
http://support.apple.com/kb/TS3727
Any WAP or wireless router, to connect reliably to Apple products, needs to support a QoS-based standard called WMM. Most if not all current Netgear products do support this. Others are not listing it one way or another. Some vendors list something called “movie mode”, but this writer has not been able to confirm whether this is real WMM, despite a discussion with vendor support.