For me, ooo how i wish I had an opportunity to have a one on one with my supervisor! Just like in all other relationships, this is so very useful ... one gets to know the other better.. yes, put a face to a name ... and even put a real being behind the persona one may have made up about the other.
With this in place, communication can thus be more open ... and deeper ...
And then there is the added advantage of being exposed to each other's body language ... and thus one can benefit from what is said .. and what is not ... but equally communicated.
However, I realize that face to face communication is a luxury for many ... and we have to make do with virtual communication. Skype and live webinars can almost be as good as face to face if one can overcome the time differences and sometimes technological challenges in the different parts of the world.
E-mails are great! I used this for almost all my supervision communication. It is relativeley reliable and I was always comforted by the fact that no matter how long my supervisor took to respond, he would eventually get back to me.... and vise versa.