Don't let language discourage you...
i agree, carlos is correct that in the upper middle classes, english is routinely spoken, and usually quite fluently, usually among those that have been college educated.
however, you will find that most of the mexicanos you will be dealing with, especially on the level we are coming in contact with in the clubs, the hotels, the restaurants, etc..., most are barely educated beyond high school, and it's quite obvious that some did not apply themselves well in their primary education. many, many girls are borderline illiterate even with respect to spanish, much less english. if you could only see the text messages i get from the girls. their spanish grammar is non-existent, their spelling terrible, and it sometimes takes considerable effort to determine what they are texting, and they're texting in spanish.
so, in dealing with 98% of the girls, the waiters, the managers in the clubs, hotel personnel, etc...your knowledge of spanish will definitely affect your ability to achieve what is achievable were you to otherwise be fluent in spanish.
however, i must admit that part of our charm as gringos is our "cutsy" ability to communicate with them. sometimes, i believe i was better off a couple of years ago, prior to being able to communicate on a level that i am now capable of. with all the communication, comes a much deeper meaning that can literally get in the way of a mongerer's primary goal.
but, that having been said about language issues, most mexicanos are very gracious, understanding, helpful, and patient. also, as wasted pointed out, sometimes half the fun is navigating a new environment. bring your spanish dictionary and have blast.
[quote=wastedgman]if you hang out in the low-end clubs area, good luck finding a soul that speaks, yet alone understands, english. but who needs it anyway? it's the fun part of being in a foreign country where you know no one and can't even tell them that you want to [url=http://isgprohibitedwords.info?CodeWord=CodeWord134][CodeWord134][/url]. yet, amazingly, you will always be able to tell them you want to f*&^k.
i would not worry about the language wickid. the nicer neighborhoods are used to tourists and speak english well enough. the upper class areas are well versed and you have to remind yourself not to speak as freely as you would in the low-end clubs.[/quote]