Indeed, and it's great that she's so clearly enjoying being out there again. A sharp contrast to the surly and sulky Zvonereva.
If Hingis keeps her wits about her against Pierce I definitely see her advancing. Pierce has improved her movement greatly in recent times and she moves very well laterally but her forward movement isn't too sharp. She is at her best with the moderately-fast balls of the Sharapova clones, which aren't typically fast or deep enough to push her off the baseline or angled enough to consistently move her from side to side. So they end up in her strike zone and she outguns them. Pierce typically loses when she comes across someone who can match her power and moves better (Clijsters, Venus) or if she can be moved out of her comfort zone of metronomic baseline bashing with varied spins, angles and dropshots (Henin-Hardenne and hopefully Hingis).