What should a good theoretical physics PhD progress look like at the beginning of 3rd year? Obviously I am asking this because I am worried!

I am a theoretical physics grad student at one of the top places in the US. The following is a brief history of my last 2 years and I would like to know of opinions and suggestions regarding the path ahead. 



I did the most advanced courses (relevant to my interests) during my first year and worked on some project ideas through very high-profile external collaborations (but the projects didn't work out and I had to can the drafts) During my second year I tried working with some other profs but the projects were never really interesting. 

[..though I have a (single author) paper on arxiv from my 2nd year work and may be I will get one more...] 

Towards the end of second year I started meeting with a very brilliant scientist who will be joining my institute as a faculty in January 2014. With him the projects are very exciting - but interactions are difficult since he is still mostly not in campus. 



Of course this unstable path happened since I had to join a grad school which didn't have people in my subject of interest. But over the last 2-3 months things have been looking up as this new person came in...
"but the projects didn't work out and I had to can the drafts" — this sounds weird to me. It is not rare at all for a project/idea not to work ou the way you would like, but for it to fail so utterly that you cannot get any work published out of it, i.e. that there is nothing for the community to learn from it, is rather rare. That it happened multiple times might be an indicator that you threw the towel too early, or that you could be looking harder into how to extract something useful from your failed attempt. Helping you out with that would typically be the job of your advisor, because it is not the easiest part of the job...

Other than that, your account does not look particularly worrying: as others have noted, you have already built a good network of collaborations, have one publication, and advanced your course requirements... Sounds good to me!