I found out two months ago that my university was sending me to Italy in a year to teach for one semester. I'll be teaching in English, but my wife and I will need to live, shop, eat, travel, and deal with random problems in Italian, so we got Rosetta Stone to help us learn.
I've read reviews here and there by people who were disappointed in Rosetta Stone, but I have found it better than I expected. Having learned one language as a child, studied four more as an adult, traveled and at least briefly conversed in six, and taught one (Latin) to kids with my own textbooks (Schola Latina), I'm almost perfectly pleased with the way Rosetta Stone is helping us learn Italian.
As another reviewer points out, the program, while expensive, costs less than a semester of Italian at many a university, and you get a lot for the money. Each of five levels has four units, and each unit has four lessons; that's eighty lessons. Each lesson includes a core lesson of about forty screens, and from four to fifteen supplemental and review exercises of five to fifteen screens. That's about 10,000 screens of exercises in the main track of the program. In addition, you get fifteen months of free access to games, stories, and interaction with native speakers, all coordinated with your progress in the program. Each level also comes with four long CDs for repetitive drill.
Rosetta Stone's special angle is that the student doesn't translate. That is, you don't respond to words in one language with words in another language. Most of the exercises are based on pictures -- cleverly clear pictures. But the program is not all about responding to pictures by choosing words, as some reviews have suggested; different screens call on, exercise, and build different skills. Sometimes you respond to written words by choosing a matching picture. Sometimes you respond to a picture by choosing a matching written word or phrase. Sometimes you respond to a spoken phrase by choosing a picture, and sometimes you respond to a picture by speaking a phrase. (The program has voice-recognition capabilities and will tell you how close your pronunciation is. You can turn the sensitivity up or down in the settings, and you can visually compare your pronunciation with the program's by clicking to see an audio graph.) Sometimes you respond to a picture or spoken phrase by typing a phrase. And in screens covering grammar, you look at a picture and choose one of two or three choices of endings, words, or phrases.
In between sessions on the computer, you can practice repeating syllables, words, phrases, and sentences with the CDs. One reviewer called the CDs useless, but I must disagree. "Fluent" means flowing, and getting the words of another language flowing out of your mouth requires repetitive practice speaking familiar phrases, just as becoming fluent on a piece of music requires playing it repeatedly, even after you know the notes intellectually.
The program doesn't shoot straight to handy travel phrases like "Where's the metro station?" or "Do you have a vacancy?" Its goal is to give working knowledge of the language, so you learn basic vocabulary, grammar, and idioms before getting to travel phrases. They might be trying to get extra money out of you by "tricking" you to buy at least two levels, but I think the approach is appropriate if the goal is to learn to read and converse in the language. After all, if you only want to greet someone and ask how much the souvenir costs, you can get a Rick Steves phrase book for a lot less.
We've almost finished Level 1, and so far we've learned colors; household objects and rooms of the house; family members; animals; clothes; eating; numbers up to 69; being cold, hot, hungry, thirsty, tired, and well; how to say where you're from, where you work, and when you do various activities; occupations; basic shopping; how to ask questions; and quite a bit more. Could we travel with this knowledge? No. But what it allows us to do is practice spontaneously with each other all day here at home, because most of our time together is spent working, eating, putting on clothes, finding things in the house, and interacting with other members of the family or the pets. And now we have the means to talk about all these things in Italian. Clever program! The titles on Level 2 suggest that we're going to learn travel phrases and more tenses (everything is in present tense so far).
Now, the program is touted as the natural way to learn a language. But note that it is named after a discovery that allowed linguists to learn a forgotten language in a most unnatural way. And remember that learning a language by repeating stock responses to phrases and pictures is only the natural way to learn a language when you're two. You still need your mother to correct you constantly: "Not 'I goed outside,' Johnny. 'I went outside.' " The exercises in Rosetta Stone introduce the student systematically to grammatical gender, conjugations, declensions, irregular verbs and nouns, rules of syntax, etc., but you have to notice the details and draw up the rules yourself. The program doesn't say, "Notice that the last letter of the word for 'black' is one thing when you're talking about a cat and another when you're talking about a car. Remember that these words represent two different categories of words called 'genders,' and note the gender of each noun you learn." If you've learned other languages before, especially Romance languages (or their mother, Latin), you notice many of these details. But if not, you might be quite confused by what seem like random inconsistencies. In any case, we teach older kids and teen-agers (and my graduate students!) a systematic understanding of the grammar of our native language, and as an adult, you should probably supplement Rosetta Stone with another cheap program that has grammar lessons. It's good to hear the varying details and and work them in to memory by rote, but it's also good to read and learn a rule for why they vary the way they do.
But if you've spent $300-750 on Rosetta Stone, you can stand to buy another $20 book. We're happy with what we're learning with Rosetta Stone and have confidence that we'll be prepared for the immersion experience a year from now.