The trend looked inevitable, but I was expecting it in Q3 or Q4... not Q1. Toyota is on a roll everywhere, and rightly so, although they likely wouldn't be my first choice in a lot of segments.
I think GM will be able to hold onto or potentially grow their sales with new vastly improved competitive, stylish products (really looking forward to the new Malibu - of all vehicles never thought I'd say that, along with others) and hopefully better direction from the top with more positive image, while globalizing more plus other ways to reign in costs.
One thing I wonder which maybe someone else can answer, is why Toyota is so big in Japan still? I know they have the traveling door-to-door salespeople, etc, but is there historically a definitive reason why they have (I believe) over half the domestic market? Also, interestingly, I think Japan would be ideal for a hybrid car (with them often stuck in intense traffic) but don't think they sell well there.