[I] This is getting kind of confusing...
But she says that since you've been putting up with this for this long, she'll give you a quick little recap:
There is still only one Rose and Roxy. They are in the Chinese Restaraunt close by the end of World 8-4; the final battle is right in front of them. And yes, this means that the Mario Intermission is close to ending. There is also only one Dirk (surprisingly) unless you count the Auto Responder. Dirk is with team Chinese Restaraunt too, and is currently still shocked about that incident when Joan kissed him. AR isn't really a physical person, but the shades accosiated with him are stuck on that one little rock sticking out in the pit that the gang went down.
John, Jade, Jane, and Jake all have one counterpart created in the inward journey: John's is Jean, Jade's is Jude, Jane's is Joan, and Jake's is Jaka. This technically means that there are two of each of them (except John; we'll get to that), even though they now go by different names. Before this, John had a one-up misunderstanding resulting in the creation of another him. This other him would then eat a fire flower, becoming FIRE John. So there are three Johns. All nine of these kids are in the restaraunt too.
As usual, the trolls don't really have much going for them. There is currently only one of them each, with one exception. Aradia, Tavros, Elitaa, Karkat, Kanaya, Terezi, Vriska, Equius, Gamzee, Eridan, and Feferi, through shenanigans, have all eventually ended up with the group of kids in the restaraunt. Sollux and Meenah are in the former's hive, Meenah arguing about the meeting she was pretty much forced to go into. The other trolls who were A1 trolls in canon (plus Elitaa's counterpart, Puerco) are just coming home from a meeting hosted by Aranea, talking about trying to kill Rip. We've only seen Aranea and Meenah as of now, the others not yet being seen due to not yet being revealed in Homestuck yet. Puerco, on the other hand, hasn't been seen yet because I'm a lazy artist.
The exception to the "one copy of each troll" statement is Nepeta, the most "impurrtant" character in Sweet Jade and Hella John. Through an ectobiological stable time loop, FIRE John helped create twelve clones of her; one with each of the blood colors in the hemospectrum, excluding her own but including Karkat's mutation. They were more-or-less split into groups but these groups have been coming together recently. Bright Red, Dark Red, Orange, Yellow, Teal, Azure, Blue, Indigo, and Purple Nepeta are all with Team Chinese Food. Green (the "original" Nepeta) was last seen through a monitor, in some kind of cave which may or may not be the same cave that the majority of Team Chinese Food went into earlier. Chartreuse, Jade, and Tyrian Nepetas remain unseen, though the latter has had a trollian conversation with Eridan earlier into the story.
And here's where things get messy: Dave. There is currently one real him and four to six dream hims. For the following reasons:
Yesterday (which took place on the 13th of Febuary, 2012), Dave went to sleep to conjure a dreamself to help him deal with some fangirls. Upon seeing a whopping nine people trying to message him at once, the dreamself installed pesterchum on itself and split into three to answer them.
One of the three dream daves used Temporal Replicsimile, splitting into two more copies: A green one that went into the past and became Past Dream DS, and a red one that went into the future and became Future Dream DS. Past Dream DS appeared in Sollux's hive and spent the majority of the 13th and the 14th there, but he has recently ended up by the house in 7-2, where Rip is. He has even more recently split yet again, becoming the cyan Past Past Dream DS and the magenta Future Past Dream DS. Meanwhile, Future Dream DS went to 8-3's inn, tried to keep Jane and Jake from following John and Jade, and resorted to splitting again into the blue Past Future Dream DS and the yellow Future Future Dream DS. Past Future Dream DS took Future Dream DS's place and would later go to Sollux's hive to replace Past Dream DS, while Future Future Dream DS has yet to appear.
Another of the dream Daves went to a dinner with his fan/hatebase, but that was on the 13th. It's the 14th now, so he could be anywhere or even dead. Same applies for the last non-temporally-displaced Dream DS, who was last seen kissing Rose in the park. Again, that was on the 13th. Hense the "four to six;" we don't know if the non-time-travelers are dead as of this point. The real Dave is still presumably in his house.