I don't know where poopsiecakes got his/her info but, no, the Catholic church didn't do away with Lent. I'm Catholic and I observe Lent every year, including this past Lenten season. Some of the rules for fasting were lessened after Vatican II but we certainly do observe Lent very seriously.
That being said, no, the Catholic Church does not change its dogmas. That is why there will never be a woman ordained a priest. That is why artificial contraception can never be accepted. That's why abortion can never be accepted. Here is an article from the Catholic Encyclopedia:
"Dogma and the Church
Revealed truths become formally dogmas when defined or proposed by the Church. There is considerable hostility, in modern times, todogmatic religion when considered as a body of truths defined by the Church, and still more when considered as defined by the pope. The theory of dogma which is here expounded depends for its acceptance on the doctrine of the infallible teaching office of the Church and of theRoman pontiff. It will be sufficient to notice the following points, (1) the reasonableness of the definition of dogma; (2) the immutability ofdogma; (3) the necessity for Church unity of belief in dogma (4) the inconveniences which are alleged to be associated with the definition ofdogma.
(1) Against the theory of interpretation of Scripture by private judgement, Catholics regard as absolutely unacceptable the view that Godrevealed a body of truths to the world and appointed no official teacher of revealed truth, no authoritative judge of controversy; this view is as unreasonable as would be the notion that the civil legislature makes laws and then commits to individual private judgment the right and theduty of interpreting the laws and deciding controversies. The Church and the supreme pontiff are endowed by God with the privilege ofinfallibility in discharge of the duty of universal teacher in the sphere of faith and morals; hence we have an infallible testimony that thedogmas defined and delivered to us by the Church are the truths contained in Divine revelation.
(2) The dogmas of the Church are immutable. Modernists hold that religious dogmas, as such, have no intellectual meaning, that we are not bound to believe them mentally, that they may be all false, that it is sufficient if we use them a guides to action; and accordingly they teach that dogmas are not immutable, that they should be changed when the spirit of the age is opposed to them, when they lose their value as rules for a liberal religious life. But in the Catholic doctrine that Divine revelation is addressed to the human mind and expresses real objective truth,dogmas are immutable Divine truths. It is an immutable truth for all time that Augustus was Emperor of Rome and George Washington first President of the United States. So according to Catholic belief, these are and will be for all time immutable truths — that there are three Persons in God, that Christ died for us, that He arose from the dead, that He founded the Church, that He instituted the sacraments. We may distinguish between the truths themselves and the language in which they are expressed. The full meaning of certain revealed truths has been only gradually brought out; the truths will always remain. Language may change or may receive a new meaning; but we can always learn what meaning was attached to particular words in the past.
(3) We are bound to believe revealed truths irrespective of their definition by the Church, if we are satisfied that God has revealed them. When they are proposed or defined by the Church, and thus become dogmas, we are bound to believe them in order to maintain the bond of faith. (See H ERESY).
(4) Finally, Catholics do not admit that, as is sometimes alleged, dogmas are the arbitrary creations of ecclesiastical authority, that they are multiplied at will, that they are devices for keeping the ignorant in subjection, that they are obstacles to conversions. Some of these are points of controversy which cannot be settled without reference to more fundamental questions. Dogmatic definitions would be arbitrary if there were no Divinely instituted infallible teaching office in the Church; but if, as Catholics maintain, God has established in His Church an infallible office,dogmatic definitions cannot be considered arbitrary. The same Divine Providence which preserves the Church from error will preserve her from inordinate multiplication of dogmas. She cannot define arbitrarily. We need only observe the life of the Church or of the Roman pontiffs to see that dogmas are not multiplied inordinately. And as dogmatic definitions are but the authentic interpretation and declaration of the meaning ofDivine revelation, they cannot be considered devices for keeping the ignorant in subjection, or reasonable obstacles to conversions, on the contrary, the authoritative definition of truth and condemnation of error, are powerful arguments leading to the Church those who seek thetruth earnestly."
http://www.newadvent.org/cathen/05089a.htm
I can't answer about other churches, just my own.
StAnn
