Majesco just sent out a very cute invitation to a Cooking Mama-themed party to be held during E3. Listed among the activities planned for the party: a chance to play Cooking Mama 3. What a nice way to announce a new game! The last "numbered" Cooking Mama was Cooking Mama 2: Dinner with Friends on DS, so it seems likely that this latest iteration will be on the DS as well.
It is very little surprise that Majesco and developer Cooking Mama Ltd. are planning another game. Cooking Mama is the cornerstone of Majesco's business, and we'd expect at least a couple of the "approximately 31 titles" the company plans to release (according to its financial report) to be Mama games. Probably more than a couple -- in addition to the newly announced 3, trademarks suggest both Babysitting Mama and Crafting Mama are on the way.