I'm in a similar boat, but with much lower grades at a UC (3.28), and a 600 on my first PGRE attempt. I'm hoping to get a publication (hopefully with a much better PGRE score by October), but it all depends on the results of my research.
It's good to get a publication, but depending on type of research, it may be difficult to get one. I got close to having a paper ready for publication, but the "nice" result that I got was due to errors in the computer code and I was back at square one. Then again, I'm extremely lucky to have the research opportunity that I have in cosmology, so I'm not complaining.
There are cases where the research may definitely lead to something publishable (some crazy examples would include developing a completely new algorithm for simulating gravitational N-body systems, or working on a giant experiment like the CMS detector at LHC). In most cases, it seems like the research is result-dependent.
By the way, if you're interested in theory, I suggest that you look for some opportunities in astrophysics. It seems like it's the best place for an undergraduate to take a crack at theory-related research, as there are (at least in my school) a lot of research projects accessible to undergraduates.