As far as I know, the blue guy and Harmonia Li are new characters.

And to reply to an older message, "Chameleon Girl" is Yera and she did indeed appear in the 80's continuity.

Gates has crossed over from the reboot universe, he hasn't been retconned in.

For the question of where it continues from: Generally, Geoff Johns wanted to continue from Crisis and Paul Levitz continued from the end of the 1980's Levitz run. There are one or two unexplained items because of this (for instance, Quislet left between Crisis and the end of Paul's 1980's run, so when Paul decided to go from the end of his earlier run Quislet's return became unexplained. It is usually assumed that everything from Paul's earlier run happened except the death of Superboy and Conspiracy (so Mon-El is still alive, for instance), though Paul has made at least one contradictory statement.

And a plug for my (well, 95% mine) continuity list for the Legion on Legion World: http://www.legionworld.ne...=get_topic;f=11;t=000644