Happy belated birthday to Brian!!! Sounds like the party was wonderful.
And, happy birthday Joanne!!! (I saw the HB thread over on Other Stuff).
Susan, glad to see you're getting some movement on the house, but sorry the potential buyers are being PIAs.
Julia, can't tell you how many times Victor has informed me that I'm "making him feel bad." If I'm scolding him for something, he'll say, "I don't like it when you talk to me that way. It makes me feel bad." That kind of talk comes directly from day-care -- they're taught to say things like that when other kids are bothering them. I also wish they'd spend some time at day-care talking about the importance of listening to what mommies and daddies tell them. Or maybe they do and he just ignores it.
Anyway, sorry you're having a hard time with the tantrums -- it sounds like Abigail is perhaps on the cusp of a developmental milestone, whether physical or mental.
Have to share this Victor story: for his birthday, one of his friends gave him a box of Superman "school supplies" -- pencils, erasers, a little lined notebook, etc. So he's been sitting down every night recently, and telling us that he's doing his "homework" -- and then he writes lines and lines of random letters in the notebook.
Last night, he gets in bed. Our routine at this point is that he's allowed to listen to a CD at very low volume after I tuck him in, and play with a "quiet toy" in bed if he's not sleepy, but he has to stay in bed. It works about 50% of the time. DH and I eventually went to sleep, but I woke up a little later (about 11:30?) and heard the CD was still playing in Victor's room. I go in to see what's up, and he's still awake, and he's sitting there in bed, with his notebook and pencils, writing away. I ask him what he's doing, and he replies (sounding very annoyed at being interrupted): "I have lists to make!" 
He's doing well at his new school. I signed him up this morning for the fall session of swimming lessons. We have a birthday pool party this weekend for my friend's son -- it's at a local Y. I'm sure he's going to want DH or I to go in the water with him. My friend said the Y encourages parents to accompany their kids in the pool at parties for young kids, even though there are also lifeguards on duty.
Helene
"We reject as false the choice between our safety and our ideals. Our founding fathers, faced with perils we can scarcely imagine, drafted a charter to assure the rule of law and the rights of man, a charter expanded by the blood of generations. Those ideals still light the world, and we will not give them up for expedience's sake."
--President Barack Obama, 1/20/09