I was wondering about the Abby and Luca thing ... I had read a spoiler that said something about Luca getting back together with Sam by this episode. I guess that spoilers was "close but off-target". They're trying to present it as "we're always there for each other" -- they really do need to be each other's friends, but Luca is not the type of guy for Abby. She's be more believeable with Duchenko, quite frankly, as Luca was more believeable with Sam. I wonder, to what extent this change in bedmate for Luca is due to audience reaction; I suspect that many 30-something women identify more easily with Abby than with Sam, so the producers feel that it would be better for ratings to have the hunk get lovey-dovey with the character that more of their target audience can more readily identify with.
My wife actually doesn't consider Luca to be a hunk -- she feels he's nothing more than puppy-dog pathetic. (I was trying to find out who she considers hunky on ER and she said that no one is, at least not as hunky as Naveen Andrews from Lost, or guys like that.) She says that the Luca-and-Abby thing makes sense because Abby can simply "read" Luca, thereby addressing Luca's biggest problem, his inability to communicate. However, in the end, all on-screen romantic relationships on ER are deliberately temporary. If they weren't, the storyline would get boring real quickly.