Gente de Mas Bed and Breakfast is THE place to stay whilst in Puebla. Outstanding service and very comfortable beds. The hostel is located very close to the Zocalo, and everything, even the fort, is within walking distance. The staff at Gente de Mas are very kind and helpful - ask them anything, and they'll do their best to help you. They are very accommodating in regards to everything - if you ask for it, they'll even lend you a towel! The breakfast is basic, but good. Toast, margarine, jam, cocopops, cornflakes, milk, coffee, tea and fruit. It's definetly possible to make a filling breakfast out of those things.
The vibe of the hostel definetly depends on whichever guests are there currently; I stayed for 5 nights, and 2 of them were filled with lots of fun, good music and general mingling with the young guests staying there at that time. The other 3 nights were much more quiet. I'll definetly recommend Gente de Mas to anyone staying in Puebla on a budget.