1) I think that the disclosure was appropriate if you two have that bond, however I think its always the responsibility of the discloser to consider the ramifications of their disclosure vs. the person who it is being told to. In my case, my T would tell me if she was in the situation - but she knows the kind of relationship we have and considers when and how much of something she will relay in perspective to where I am and how my knowing would affect me.

2) I don't think that after todays session you will need to be as gentle. I get the feeling of obligation to be nice, but in my experience, the disclosure should not come up in more than one more session and therefore time and continued sessions should automatically ease you into getting back to "your norm". You are still the client, and disclosing this news to you is fine but turning into a weekly session about how it is affecting him is for him and his own T, especially if it is affecting him greatly.

3) I think a sympathy card is both compassionate and appropriate.

These are all my opinions, take them with a grain of salt.