updates:

03.02.2014 - 62 squares so far
11.02.2014 - 80 squares total

I used the flat crochet seam joining technique, worked really good, though there were very many ends to weave in (and I used a 3 mm hook). I also used another color for the last 4 edging rows (and a 3,5 mm hook). I am very happy with the result, because this was also my very first blanket made out of squares :D