Update 2: Gabe Newell released a statement on the recent firings to Engadget saying:
We don't usually talk about personnel matters for a number of reasons. There seems to be an unusual amount of speculation about some recent changes here, so I thought I'd take the unusual step of addressing them. No, we aren't canceling any projects. No, we aren't changing any priorities or projects we've been discussing. No, this isn't about Steam or Linux or hardware or [insert game name here]. We're not going to discuss why anyone in particular is or isn't working here.
Update: According to Gamasutra, several people were let ago from Valve across different departments from hardware to Android development due to "company challenges" rather than individual employee performance. There is still no comment from Valve and let go employees have been asked to refrain from talking about specific details.
Yup. Got fired today. Time for new exciting projects.
The corporate structure of Valve and the office environment (at least from what we're told about) makes this a very intriguing story because it doesn't seem like someone of her talent would just be fired. Ellsworth was hired around April 2012 to work on "next gen gaming hardware" only to be let go almost a year later. This coming after two big talks from Gabe Newell (Interview with The Verge at CES 2013, and D.I.C.E. Summit 2013) about his company's vision on PC entering the living room in the form of a console.
Ellsworth has created a big following from her Youtube channel posting about various hardware engineering topics including her bass guitar made from a Commodore 64. As I mentioned above, she is a self taught engineer and talks about how she got started in an interview from 2011 at the Embedded Systems Conference (ESC).
Engadget attempted to contact Ellsworth and Valve to comment on why/how she got fired but there hasn't been much public response other than Ellsworth posting a tweet with a picture of her homemade pinball machines lined up ready to be taken home. I will be following this story if it unfolds.