Just to add some input. These always get confused.
Recording means recording is supported. Still need a 3rd party recording server and need phones that have the dual-RTP stream capability. See the administration guide for the supported phones. Usually 79x1 and up phones.
Intercom is actually paging to ONE phone. If the phone is on the phone (hehe) the page can be "wispered" so only the IP phone can hear the page. The person they are talking to can't hear it. Like auto answer to speakerphone from previous CCM versions, need a phone that has a free line button (ie, 7940, 7960, etc.) 7906, 7911, etc with only one button is not supported.
Another big one is AAC / ILBC codecs. AAC is higher fidelity voice. 22KHz, 16Bit instead of 8K, 8 bit. All using the same 80Kbps transfer rate. Need the newer phones to support it (7942, 7962, 45, 65, etc.) ILBC is a codec that is supposed to be more, say, Internet friendly. Tolerates more jitter, latency, etc. Also need those newer phones.
Do not disturb: A real do not disturb
what else is good.
Programmable line keys. A line key can be programmed to take on just about any (one) function. Line, Speed Dial, BLF, hold, transfer, etc.
Upgrading from 5.x to 6.0 is a little "different" since the database changed significantly.
