This depends on your perspective however. There are pictures of Emma in 2009 (see below), where she looks pretty thin. Her arms are thinner here than they are now.
In 2010 (playing field hockey) she looked pretty thin.
Now in 2012, she looks fairly thin again. She looks absolutely fantastic! ... but thinner than she was maybe last winter or last fall.
Is it possible that the weight Emma is at now is her "comfortable" weight? Maybe she was overweight before and now is back to her normal weight again. It depends on how you look at it and what perspective you take. The bottom line is that she looks drop dead gorgeous lately. I don't think she ever looked better to be honest.
The people that don't like her will always take the negative perspective. This is the definition of cognitive dissonance Echee!
Emma Watson and tanning - Emma sounded like she was whining a bit when she talked about what she was not allowed to do while filming Potter, but she wasn't really deceptive about it. She couldn't change her appearance in a way that would change Hermione while they were actually filming the movies.
Echee has a whole bunch of pictures where Emma looks tanned.
1. These pictures were not taken at a time when they were filming Potter.
2. Emma always used tan spray. It doesn't last that long.
Emma at the DH 1 Part Premiere (London)
Emma the next day in New York
The fake tan crap wears off pretty quick Echee!