I have only had one, but it looked pretty bad. I had four six packs of 12 ounces bottles conditioning inside of a box to keep things light tight. One of the bottles exploded at some point, and tiny shards of glass were all over the box. A few were stuck into card board. I had to rinse the other 23 bottles since all were sticky, and toss the box and 6 pack carriers.
I would not have wanted to be within line of site just looking at all of the tiny glass shards (think shrapnel). Assuming that I either had a weak bottle or single bottle infection on that batch though, all the rest were fine.