you pick the dessert, that's why it doesn't list it. For example, at Flametree BBQ in AK, the BBQ ribs platter comes with beverage, ribs, baked beans & a corn muffin. You choose dessert - there's key lime pie, Min Maid Frozen lemonade & I think carrot cake (but maybe apple something?) Anyway, point is, it's a platter/combo meal and you still choose dessert. One thing to remember, the allears.net menus & the wdwinfo.com are not official Disney pages...all the info is provided by volunteers & may or may not be accurate. We use them as a general idea, not exactly what's what.
We have been to WDW this year (2009) on the Dining plan and I can vouch that you still get dessert...most places you choose the dessert. Tangierine Cafe (Morocco/Epcot) is one place I know for sure that it's a set dessert that comes with the platter meals...you get baklava. I think one of the Asian restaurants on World Showcase might also have a designated dessert. And I'm thinking the giant fresh hot chocolate chip cookie comes with the pizza combo at Toy Story Pizza Planet/DHS. But everywhere else we've ever had counter service lunch you had at least two items to choose from for dessert...and some places like resort counter service you might have at least 1/2 dozen choices.