Yes, but you also see a lot of non-Angels on the website and doing launches. As for promotional, like tv-shows and for example accepting awards that's what only Angels do. And they really left Miranda out of that part of the job of an Angel
I usually just lurk, but I have to respond to this.
Launches this year off the top of my head
Alessandra - Facebook/webby awards, BBV
Adriana - Vintage Victoria, SLT Nor
Marisa - Naturally VS, BBV, Swim 2009 with Shape Magazine
Heidi - Perfect One
Doutzen - Vintage Victoria, Facebook/webby awards
Miranda - Heavenly Bloom, Heavenly Enchanted, Dream Angels bra
There was also something back in May that Heidi and Miranda did together for parfums intimes and mother's day where they were interviewed for Good Day LA and E. This year Miranda's also done Carson Daly, went to the Costume Institute Gala, and the ESPYs. What have the other angels done that's so significant that makes it seem like Miranda's getting left out? I don't think she's used any less than any of the others.
As for Lindsay at the BBV launch, I wouldn't read too much into that. I think history has shown that appearing in the catalogues often and doing launches/commercials does not mean the model is destined for angel status - Oluchi anyone?
Besides, they don't necessarily have to drop any angels to bring someone else onboard. At the time of the 2005 show, they had 8 - Tyra, Heidi, Gisele, Adriana, Alessandra, Karolina, Selita, and Izabel. They ended 2006 with 7 - Heidi, Gisele, Adriana, Alessandra, Karolina, Selita, and Izabel. They ended 2008 with 8 - Heidi, Adriana, Alessandra, Karolina, Selita, Miranda, Marisa, and Doutzen. They could sign two more models right now, and it would put them at their late 2005 and late 2008 angel numbers. If Heidi were to retire in the process, they'd have 7 - same as the end of 2006.