Lifesta isn’t the only newcomer to the dining-discount game. Opentable just launched Opentable Spotlight, a “weekly chance to buy a delicious deal (typically half off!) at a top OpenTable restaurant.” Sign up for deal alerts, then buy into the deal of the week, and (à la Groupon) if enough people participate you’ll unlock a gift certificate that you can print out and take to the restaurant. The service launched in Boston and New York (with more cities to be added) and the current deals are available till midnight: $25 for $50 worth of dinner at New York’s Metrazur, and $25 for $50 worth of food (valid Sunday through Thursday only) at Boston’s Ginger Park. With the advent of Yelp’s new Daily Deals feature, it looks like Groupon is in for still more dining-discount competition.