Last year the sports drink was in cups and unbranded, red in colour I think, very nice though. Also the oat energy squares were very good. There was a little test tube of something in your goody bag at registration and they also gave them out after the race. My German isn't that good so I couldn't make out if it was to drink or rub somewhere.
I have looked back at my bank statements and the payment was taken by a company www.amiando.com They have a website in English but no details of events they are taking payments for. Might be worth contacting them to see if they are taking entries for the marathon this year
I did the Munich Marathon last year. There was an English Version of the website although it wasn't available straight away, I think I entered online in February.
It was only my second marathon and I loved it. German efficiency with the organisation ( I did the Birmingham half a fortnight after and what a shambles that was compared to Munich).
It didn't seem hilly when running it but when I looked at the stats on my Garmin after the race it appeared we had gone up and down quite a bit.
The support was great and finishing in the Olympic stadium was a fantastic experience. All kinds of bands playing round the course, the German heavy metal version of Rhianna's Umbrella was a particular highlight.
The stadium is out of the city but has good underground links to it. You have to go to the stadium on the Friday or Saturday to sign in. We stayed at the Inetrcity Hotel by the main station that gives you a free tube pass for the length of your stay.