Evan,
Can you explain a little more about what you're looking for? The Like and Send buttons for Facebook have to direct the user to a URL, if they click on it from Facebook. The activity stream in JomSocial may just be a comment a user makes. That means it may not have a real URL to go to, or anything a user in Facebook would really understand what to do with the Like/Send if they received it.
Because of this, it makes it very difficult to add the Like/Send button to each activity because there's not much to 'do' with individual activities.
Hope that make sense, but if you have suggestions or ideas, just let us know!
Thanks,
Alex