With Avatar's release last year 3-D became the instant "big thing" in Hollywood and so far it's resulted in some disappointment. Tim Burton's Alice in Wonderland did extremely well at the box-office, but most of that could easily be due to Johnny Depp, the 3D was panned by most reviewers.
Post conversion attempts such as The Last Airbender and Clash of the Titans were both met derisively for both their plot and 3-D, so not a successful venture either way. Most filmmakers are learning that post-conversion just isn't working and have decided to film with 3D cameras instead of making the hasty, grimy and often unappealing post process.
Saw VII, Jackass 3D, and the rest of the offerings are expected to just more of the same, tired pop-out schtick that has been passed off as the real thing for years.
One of the films being released made in production with 3D cameras is Tron Legacy. With that said that's why Tron Legacy is the first big picture I'll be looking forward to in 3D for the rest of the year. The 3-D for Toy Story 3 was nice, but nothing beyond the mainstream. I haven't seen How To Train Your Dragon so I could not speak to that. The only time that seeing the third dimension in theatres was a big deal was when I saw Avatar last Christmas. Hopefully, Tron Legacy will be more of that same full-immersion 3-D that James Cameron blew collective cinema-goers mind's with.