Yeah, I thought they were quite different as well:

```
# grep 'platform' * | awk '{print $3}' | sort -n | uniq
debian-6-amd64
debian-7-amd64
el-5-x86_64
el-6-x86_64
ubuntu-10.04-amd64
ubuntu-12.04-amd64
```

All mine are consistently at the beginning of the string and hyphen separated also.