Based on a short but probably-representative sample, these are all the hostnames that rounded to >=1% of all address (A/AAAA) queries.  Between them they totaled ~57%, leaving ~43% for the long tail:

1% pt.wikipedia.org.
1% ja.wikipedia.org.
1% es.wikipedia.org.
1% fr.wikipedia.org.
1% de.wikipedia.org.
1% maps.wikimedia.org. # Note upload-addrs, not text-addrs
1% ru.wikipedia.org.
1% commons.wikimedia.org.
1% zh.wikipedia.org.
2% wikimedia.org.
3% wikipedia.org.
7% meta.wikimedia.org.
8% login.wikimedia.org.
8% www.wikipedia.org.
9% en.wikipedia.org.
11% upload.wikimedia.org. # Note upload-addrs, not text-addrs