Thanks again everyone for responding to my questions. It really looked pretty bad.
After six weeks in a cast (2 weeks with my foot stretched, then 4 weeks with the foot at a 90 degree angle), I am to wear a stocking that will support my leg and foot.
The muscles in the left leg have deteriorated tremendously (which also looks pretty silly). Not to mention the farmers' tan

But hey, that's noting, right
The healing process went very well; the tendon has reconnected and shows no evidence of discontinuities; it's just your regular achilles' tendon. Yet, it is still stiff; I cannot lift my toes as far up as with the "normal" foot.
Then again, my surgeon was surprised at the speed at which I am regaining the function, so now I can go and swim daily (for two weeks) and after that he wants me to go ride my bike (for another two weeks).
After that, I should be able to walk normally and we'll look at the situation then. It still might take some physical therapy, but we'll see in a few weeks.
Most importantly, my surgeon indicated that I will not have any negative drawbacks where it comes to future diving and sports activities, barring indoor sports (squash, indoor soccer, that kind of stuff). Explosive movement on hard-top surfaces might be a little tricky, but abseiling with 50 kg of diving gear and entering the water with it's uneven surfaces should not be a problem at all (hurray !

).
Thanks again for the moral support I'd been getting here !