This is surprisingly doing rather well on amazon japan's pre order rankings.
Right now...
http://www.amazon.co.jp/gp/bestsellers/dvd/ref=sv_d_3
Tiger and Bunny Vol 1 is #7 and Vol 2 is #30.
Steins;gate vol 1 #56
Hanasaku vol 1 #88
Steins;gate vol 2 #91
Denpa Onna vol 1 #93
IS Vol 1 after 3 weeks only hit #28...
Anyway Steins;gate has a massive points lead at the moment but Tiger and Bunny is the clear #2 atm from shows with release dates. Even though Vol 1 is cheap, seeing Volume 2 high up is encouraging.