I'm sort of in the middle on this issue.
I don't think that simply washing glassware or cleaning up the lab should be considered research experience... or, at the very least, it shouldn't be viewed on the same level as the experiences of an applicant who was actually involved in the scientific process. In my personal experience, I knew several of my classmates in undergrad joined a lab to do these duties just so that they could say that they had research experience on their professional school applications. I don't think that that's right and I'd imagine that most schools see through that sort of thing.
If you're actually helping to gather results, interpreting them, writing proposals/publications, presenting at a conference, or even organizing and doing your own project... those are far more legitimate experiences that I would definitely say are worth listing. These are also the types of research experience that I think most schools value. I don't really agree that there necessarily has to be a paper published in order for it to be significant, but there is no denying that it helps if you can achieve authorship and there is considerable clout that comes along with something like that.
As an example, my research experience consisted of running statistical tests on gathered data, giving an oral presentation at a statewide conference, and writing the Abstract of the paper that we looking to publish in an ecology journal (I don't think that ever actually happened, unfortunately, as my PI has since passed away and I don't know that anyone is going to further seek getting the research out). But schools that I applied to were really, really interested in those experiences and I was able to talk about them at great length.