He is definitely at the two-word stage. He is producing Verb-Object, Subject-Verb, Adjective-Noun, Possessive-Noun, Quantifier-Noun, Modifier-Adjective , but not yet stringing those together into larger sentences. The complete sentences I have heard so far are things like  `Mamma ta den' (Mama take that), and De e Viva's (That is Vidar's).   He has a particle construction Eter upp den.  
Negation is interesting. He seems to have both inte  and jo  as discourse particles for negation and affirmation respectively. They do not come in a particular order, but can be attached either before or after his (usually 2) word sequence. So they do not seem to be very syntactically integrated yet. The other day he used inte to negate an utterance, and then repeated the whole thing using not  instead, so he knows those two are equivalent.
When it comes to English and Swedish, he translates freely between them but speaks mostly in Swedish. He seems to think they are the same thing at some logical level.  As a party trick, it is possible to ask him literally ``Can you say strawberry?''  Or ``Can you say car?'' and he will respond with jordgubbe and bil respectively.
He understands the letters of the alphabet and will recognize and name A, B, C, P, M, V  at least.  He will also volunteer words that begin with these letters. Whether this is phonological understanding or just rote learning I do not know.  He often goes out of his way to ask for the ABC book, or the ABC puzzle.
I have mentioned already that he has no distinction between l/r/y and they all come out as /y/. He seems to have generalized this. He has now noticed the existence of /r/ at the ends of many words like Vidar, and all the Swedish plurals. He has started pronouncing these words with an endglide, so that Vidar comes out as vivai.  Here and there (hær and dær) have been hai and dai for a long time though.
Vidar can count to ten more or less (in Swedish) which is just by rote, but he definitely actually understands two  and also three.   You can ask him how many X's there are, and if it is two or three he will count, and give the right answer. With `two'  he doesn't even need to count.
Here are some more common phrases, before I forget:
aya dom  (all of them)
baade toe (both of them)
kan de  (can (do) that)
min  (mine, used predicatively more than attributively. De e min )
inteting (ingenting, nothing)
 Some cute things: When he jumps down off of something he often says Humpty Dumpty as a joke (He  decided that one himself; all I ever did was read him the nursery rhyme).  He likes the Cat in the Hat books, and even the Cat in the Hat Comes Back.  He keeps bringing it up, and spontaneously mentioning Thing1 and Thing2, and Voom.
Right now he is into the CD we have of Astrid Lindgren. He says `dansa Pippi'   when he wants to hear that CD, and then there are 4 or 5 songs he likes to listen to and dance to including the Pippi song, Emil song, the Pirate song and some song about a cat.  These songs really can't be listened to that many times, so Bjorn is going a little crazy.