The Vatican has allowed it so that anyone can recieve communion however they like: in the hands or on the tounge, kneeling or standing.
However, the Vatican made it clear that the "proper" way, and the preffered way to recieve it is kneeling and on the tounge. The ability to recieve it in the hands and standing is a dispensation that only applies to a few western countries. They created this dispensation with the condition that anyone can recieve the Eucharist any way he or she pleases, and it is entirely up to individual discretion.
Priest's, deacons, and extraordinary ministers of the Eucharist understand this rule as part of their training. So it wouldn't surprise them at all if someone were to kneel and stick out their toungue to recieve the Eucharist. They would know what to do.
There may be some more traditional parishes (like Latin mass communities) who refuse to give people Eucharist in the hands, only kneeling and on the tounge. This is breaking the rules, but it isn't as serious, since, as mentioned, on the tounge is the preffered way anyway. If someone goes the other way, and refuses to give people eucharist on the tounge and only in the hands, this would be much more scandelous, and the issue should be taken up with the bishop.