Believe what you read in the other three reviews below. My wife and I stayed for a week.
The rooms, breakfast, service, cafe outside the front are all very good (and probably will exceed most peoples expectations). The setting and location is perfect.

People who hear the word 'Armenia' and think 'oh my god' have nothing to fear.

A tip for the blokes - a pint of beer is as little as 45p.

The Marriot is certainly a good hotel in terms of rooms, service and location. The set-up of the hotel is a bit odd, with the main wing being located a hundred metre walk (through corridors) away from the main reception. However, the rooms are excellent, kind of junior suites. The restaurants are good and so is the the breakfastt. Location is very good, too right in the centre. Given that there is not that much competition in Yerevan, it is surprising how good the Marriot actually is. Definitely first choice.

My wife and I recently spent a month at the Marriott Hotel in Yerevan. We had previously been staying in an apartment without air conditioning, but the ferocity of the Armenian summer finally defeated us and we decided to move. Given the amout of time we intended to live in an hotel we spent two days visiting every major one in the city centre. If you assess its appeal on a purely numbers basis, dollar per amenity/bedroom space/service/luxuriousness, etc., then the Marriott has no competition in Yerevan - you get a lot for your dollar. If you consider its location on Republic Square then money can't buy you anywhere better - it's the equivalent of Leicester Square or Times Square but with a manageable number of cars and people.

More than that the rooms at the rear of the building have balconys (yes, 2 per room) and spectacular views of Mount Ararat (above about the second floor I guess). They also have, in addition to the bedroom itself, a separate living area (big enough to hold a small party in), walk-in wardrobe and large bathroom. This is a standard room. No other hotel that we visited came close to this level of luxury.

One other small attraction; the Italian restaurant, Cucina, on the first floor not only serves very fine food, it also lays on impromtu live entertainment in the form a a singing waiter (if he's still there), who performs for about 5 minutes a night. Peculiar but fun.

The original site of the Hotel Armenia; it took several years for the Marriott Corp. to upgrade the facility and get service standards up to par. All the rooms are suites with king size beds and the room floors have secured elevator access. Two good restaurants (Italian and European/Armenian) and the ballroom are used for major social events including the annual Burns supper sponsored by the British Embassy. The Hotel sits prominently in Republic Square and is within walking distance of many restaurants, nightclubs and shopping (including the main outdoor Vernissage which is open every weekend). Highly recommended and it's probably the best value for the money.