If I'm honest, I think the story succeeds more in terms of mood and tone than plot. The story rushes along, with very few explanations. The whole immortality-giving flower thing feels so isolated: it shows up in this story, and is gotten rid of by the end.
The back of the book is taken up by the second half of the Robbins/Kane Robin solo story. I don't really have anything to add to what I said about the first part: it still has the feel of a writer struggling to appear contemporary and relevant without actually being part of the culture he's writing about. The story uses campus protests as the main part of the plot without appearing to understand the politics of those protests.