Hi guys, I needed a gradual ease into orbit, and it turned out easy and nice at the end:

[youtube]j71pbjYBDpE[/youtube]

The trick is to create a copy of your particles (not renderable), reference them to the original ones, then orbit the copy and, in the right moment, use bringto with the referenced data to bring the parent particles to the child ones. Another cool day at TP land!