Everyone I know feels that "accepted / in press" is just as good as appeared: the delay between acceptance and publication has nothing (or anyway, too little) to do with you. You should certainly list them on your CV, no matter who you are. I don't even list these as in a different category as the ones which have already been published: the only difference is that (roughly speaking; electronic publication and DOIs complicates this somewhat) I can't tell you the bibliographic information if it hasn't appeared. I think it is very important not to list a paper as accepted without listing the journal, because therein lies the route to verifiability that your paper has been accepted.
In my opinion, you should list submitted articles on your CV no matter who you are. (I would be interested to hear why @aeismail feels differently about this.) This advice comes from someone who works in a field (mathematics) for which recently submitted articles ought to be freely available: if you want to get credit for having submitted an article, then whoever you are trying to get credit from ought to be able to see the article. Ideally they don't have to ask for it specifically (because maybe they won't), so you should include a weblink to submitted papers on your CV. (This last part is more for people who are in a potential-hire situation...which is not restricted to grad students and postdocs. Nowadays, lots of academics are in a potential-hire situation or would like to be.)
In mathematics, each paper takes a long time: the period between when you say "Aha, I can prove the theorem" -- and e.g. start to give talks about it -- and the period which it gets accepted is probably over a year in many cases, and closer to two for serious, important work in many cases. Who is reading this part of your CV and isn't interested in what you've been working hard on for the last year or two?!?
Whether to list the journal submitted to is a well known question mark. I do not put this information on "external" documents -- i.e., the CV and the publication list which are on my professional website. I do usually list it on "internal" documents -- annual reviews, grant applications, job applications (well, it's been a little while). There are a lot of nuances here: one is that it is really hard to know how much credit to give someone for submitting a paper to journal X. After all, anyone can submit a paper to the most prestigious journal in their discipline, and in many cases they will spend a nontrivial amount of time before rejecting you. So you want to be careful about this. Nevertheless, where you submitted a paper is an important piece of information about how you feel about the paper, which is worth including in various cases (e.g. grant applications, where the panel will be suitably skeptical). Another issue is that one commonly submits to more than one journal (not at the same time, but in sequence) so the information about where you submitted a paper is likely go out of date, so is less suitable for a sporadically updated CV and more suitable for a CV guaranteed to be complete up to such-and-such a date.
Note also that in my discipline, many people -- especially young people but not always -- also include papers which are "in preparation" on their CVs. This is, frankly, a little shaky: I have papers on my own CV which have been "in preparation" for getting on a decade. But the above philosophy still applies: if you've been working on something for five years and you're 75% done, then shouldn't you say something about it?
One last piece of advice: it behooves you to make absolutely clear the distinction between all these categories. I get annoyed as a hirer when people use categories that don't fit easily into any of these boxes: e.g. some job candidates list papers as provisionally accepted, conditionally accepted, or accepted pending revision. What a hiring committee litmus test that becomes: their proponents will insist that these be counted as actual publications, their detractors will insist that they don't count as any more than submitted, and people in between will get a headache.
(I don't mean to imply that it's necessarily the candidate's fault. Sometimes the journal tells me that my paper has been provisionally accepted, and when I need to create a CV for a grant application that gives me the very same headache: please give me a paper status that has a clear, unambiguous meaning! They do enjoy their little games, the journals...)