According to the official twitter, the final episode of Bakemonogatari will be streamed today (i.e. June 25th JST) in the official website. It was scheduled to be aired in the mid-June.
Source: Bakemonogatari official twitter
Updated
The streaming of the final episode started at 11:55pm.
Bakemonogatari streaming site pretty heavy as expected
According to the official blog, the OP animation will be completed next week. Meanwhile, a live action version of the OP will be aired instead.
Source: Bake official blog
