I think this is a really positive move by the Emercoin team. EMC has been going from strength to strength since inception by releasing many unique services, and as EMC is already using sha256 mining, merge mining with Bitcoin should bring added security, more awareness, and greater adoption.

At first I wasn't sure as there are several other coins that already can be merge mined with Bitcoin, but I think it is a good idea.

There's a good technical description of merge mining at https://en.bitcoin.it/wiki/Merged_mining_specification

This is also my first steemit post :)