I wrote back to the agent who sent the most recent rejection to thank her for her time and lovely compliments and such. 

I also mentioned that I have come up with a few ideas for revisions for Seth's story (which I listed briefly), but I haven't yet gotten to the point of tackling them since I'm focused on writing a new novel right now.  I didn't say, "Would you be interested in this revision?" but, of course, it has to be obvious that I'm wondering or else I wouldn't have told her my potential plans.

She wrote back this morning saying Definitely keep me in the loop if you revise this one or plunge forward with a new novel.

So... what does that mean?  I'm sure she doesn't want periodic updates from me.  "Hi, [Agent]! I'm currently plunging forward with New Novel." 

"Hi, agent!  I put a few hours into revising Seth's story over the weekend.  I hope to be done on [whatever date]." 

I mean, come on!   She just wants me to let her know when I'm finished with one or the other so she can tell me if she wants to read.  Right?