Sony recently announced that they will end production of the original Beta format cassettes that were amazingly still in production in Japan (and apparently only sold there as well). The writing was on the wall for the format, especially as they haven't made a recorder with standard size tapes since 2002, and ended production of the micro format recorders in 2005. Here's more from Sony on the format that's been around since 1975 (translated from Japanese):

Sony in March 2016 ※ with a, we will end the shipment of beta video cassette and micro cassette MV. 
Beta video cassette is a recording medium of magnetic tape recording method "Betamax format," which was developed towards the video recording applications for the home, we have been producing since 1975. Production of same-format video tape recorder equipment has been completed in 2002. 

Micro MV cassettes, in the recording tape media of digital video camera recording method "micro MV format", the production of the same format compatible video camera has been completed in 2005. As a result, the recording media of the Betamax format in our company, and shipping of the recording medium of the micro MV format, it will be all to end. ※ There is also a case to terminate the previous plan period by the demand situation.

And here are the tapes they will stop making:

Beta

  • EL-500B
  • 2L-500MHGB
  • 2L-750MHGB
  • L-25CLP (cleaning tape for beta video)

Micro MV

  • MGR60
  • MGRCLD (cleaning tape for micro-MV)

Though many like to make fun of the format, Sony's Betamax produced superior quality over VHS, but were initially limited in recording time. That was one of the reasons VHS took over — not because it was better — but because it was more convenient for recording longer programs, like a two hour movie. While Sony did eventually produce longer-run Beta tapes, it was already too late for the format on a large scale, which is why it's crazy they were still producing these tapes at all. 

The Beta format does live on in some ways, as you can still get Betacam and DigiBeta tapes — though none of these newer formats are compatible with the original recorders or players. I'd be surprised if any professional applications were still using the original Beta tapes, especially as the updated Beta offshoots were higher quality with better features. This is the part of the story that people don't seem to realize, as Beta lived on much longer as a format than VHS did in the professional world, especially in cameras. 

All hope is not lost, however, because if there is enough demand for these tapes, Sony may continue producing them even after March 2016. I don't see that happening but anything is possible. 

Source: Sony Japan

Sony
Cinematography & Cameras