Since the thread linked below had so many good ideas, including my favorite salsa of the night, Eat Nopal's Roasted Tomatillo, Garlic, Ancho & Arbol Salsa, I thought I'd report on how it turned out (and hopefully get the other CHs to report on what they brought!)
There were 16 of us and WOW what a great meal we had with everybody contributing. It really was a delicious menu, with friends also bringing wonderful Spanish wines and making margaritas to accompany this feast. Great company and great food - what more could you ask for.
Menu with linked recipes:
Picadillo empanadas with cilantro crema (crema mixed with sour cream, cilantro, lime juice, and some Penzey's Adobo seasoning).
Guacamole, chips, and 3 salsas - salsa borracha ("drunken") with guajillos, tequila, onion, and garlic ; roasted jalapeno and tomato; and Eat Nopal's Roasted Tomatillo, Garlic, Ancho & Arbol Salsa
Steak, avocado, and salsa verde tostaditas
Sauteed Shrimp in Latin Citrus Sauce
Pork, beef, and chicken tamales
Slow-roasted Yucatan pork
Corn and flour tortillas/queso fresco/cilantro/crema
Chili Rellenos. Note to self: Remember to take toothpicks out BEFORE you serve it to your guests ; ). Rick Bayless http://www.recipezaar.com/56452
Mexican rice, ceviche, chicken, and machaca
Topolo Caesar salad with green chile, lime, cilantro and queso anejo - from Rick Bayless' "Mexican Kitchen
Frijoles Maneados - Refried beans with cheese and ancho chili
Chocolate Bourbon Cake with Caramel Whipped Cream http://www.chowhound.com/topics/356047
Mango and lime-curd tartlets
Along with Coronas, Spanish wine, and both classic and frozen mango margaritas, we had a good stash of reposado and añejo tequilas from our trips to Mexico, and after-dinner liqueurs. Don Julio, Herradura, Tres Generaciones, Tres Mujeres, and 4 Copas. Patron Cafe, Dobel tequila con cajeta, and Don Julio 1942.
For Boston locals - I picked up fresh-made corn tortillas and chips fried to order from the Cinco de Mayo factory in Chelsea.
I only took a couple of pics, but hopefully another 'Hound will post more.
Roasted Tomatillo, Garlic, Ancho & Arbol Salsa, Lime Curd and Mango Tartlets, and Chocolate Bourbon Cake: