It was apparent to us after a very short time on-board the Mediterranea that Costa are trying to claw back as much money as possible after the loss of the Concordia, through rigorous cutbacks in all areas of service. The food was average at best, and diabolical at worst. The communication with passengers on excursions was non-existent and on several occasions we would have been left behind or missed one of the sights/activities had we not actively sought out excursion leaders for information. The ship was dirty and has seen its best years. Our cabin had a rotten carpet and no amount of shampooing from our poor steward would eliminate the smell (no upgrade or cabin relocation was offered).
At times, and in the restaurant on decks 2 and 3, the food was acceptable, if uninspiring and heavily pasta-based. As others have said about Costa, one would at least expect the pasta to be well done, but it was usually cold and rubbery. Service was slow, and we often waited 30 mins just to get water. We were unlucky enough to be seated with another German couple whose names we never learned and insisted on using only the stuffy "Sie" form for conversation, which further detracted from the dining experience. Not Costa's fault, but we tried unsuccessfully to be moved to a table for two.
Breakfast on decks 2 and 3 was acceptable, but the service was poor and very confused most of the time. It took a long time to get a simple order of eggs, often requiring us to chase lost orders and usually receiving someone else's eggs cooked a different way to how we ordered them.
The buffet restaurant, however, was consistently simply appalling. It served the same limited menu every day for the entire cruise, for both breakfast and lunch. The scrambled eggs tasted artificial or pre-prepared. There was only one variety of pizza available for those that didn't want to attend the restaurant (margherita). A real let down compared to the buffets we have experienced before on both MSC and Costa vessels.
Our cabin had a rotten carpet due to an AC leak, which resulted in a constant rancid smell. After complaining, instead of being moved or relocated, the steward was unfairly tasked with shampooing and drying it with a huge fan daily, which made no difference to the smell and only served to be a further inconvenience to us.
The onboard activities consisted of very loud games on deck 9 for the (already loud enough) Italians. The shows in the theatre ranged from badly rehearsed and poorly produced to mediocre. The opera themed around the Costa Meditarranea included a background film of the ship and its singers, which amounted to nothing more than an overly sentimental, back-slapping exercise for its egotistical "stars" and a thinly-veiled protracted promotional trip for Costa cruises. Best avoided completely.
One of the highlights of the Costa Mediterranea is the glass staircase at the top of the (admittedly impressive) atrium - but this was closed for the entire 10 days we were onboard. Again, a big disappointment.
The highlight of the evening entertainment was Ron, an English guitarist/one-man band, who an excellent, witty performer who regularly invited the audience to participate with him and genuinely enjoyed the interaction. He brought a real human touch to the entertainment, which was otherwise completely lacking on this characterless cruise.
This unfortunate experience has put us off Costa for life and cruising for at least a few years. The German activity leader Paul was utterly disinterested in our complaints, seemingly acting as a kind of sounding board for the plethora of displeased German-speaking passengers, and with no influence or ability to improve the dire situation onboard. We gave up complaining to him after a couple of times.