Just some observations from the day ...
The a450 may never see the shores of the good ol' USA. It looks to be being market exclusively in Eur/Asia.
I went to the SONY Style store, tonight, and review things as they have been happening there. There is no word of any α450 stock up.
I then reviewed the α550, as they had one in the case ... and it was rather disappointing, in contrast to the α700/α850/α900 selections, of which I am VERY familiar.
Albeit, one of the novel things, though, was the 12.800 ISO setting. I shot that through the 18-55mm f/3.5-5.6 "kit" lens, just to see how the NOISE response was ... and doggone it, it's not bad. It is very similar to the α700's ISO-3200, so definitely a better sensor response and process.
But ISO, alone, does not make a body. The α550 is definitely harder to get the same comfortable grip with, that I do with the other cameras. Admittedly, all my cameras have a vertical grip, but still ... it feels rather small in my hand. I would not consider it as anything other than someone else's choice, not mine.
Over all, I am so ready to see a SONY α7xx come to market, with better focusing and noise response. That is what I would be saving my money for, not an a500/a550.
I do not like the idea of anyone going broke to produce excellent photographs with these devices, but I also realize that it has never been cheaper to do it. There has never been a $2000 Full Frame DSLR until the α850. The α700 was down to being so cheap, it came in at $300 under the α100 release price, back in 2006.
Personally ... SONY photography, in 2009 was about as cheap an entry into good DSLRs as we will probably EVER see. From here it is nothing but going back up and up and up.