ECM is only available now to those who is subscribe to RH. Its not yet available to the public. Also that screenshot may well be ACS Tcl, as you can observe the address location is not present. There had been many screen shots given by aD previously claiming it was CCM, where in fact its ACS Tcl because the URL gave it away.
CCM is a fine platform, but as of now the one that is available to the public is just the core and CMS. ECM and postgres support is not available for the public yet.
Here is their release policy of the code:
If you need something now and only have few developer resources OpenACS is a good choice. If you have a lot of developer resources, keen on using Java and willing to pay RH. CCM is also a fine choice.