It is the actual physical body and blood of Jesus Christ to us.
Since I am a Southern Baptist, I am to adhere to the Baptist Faith and Message, which says on this subject:
"The Lord's Supper is a symbolic act of obedience whereby members of the church, through partaking of the bread and the fruit of the vine, memorialize the death of the Redeemer and anticipate His second coming."
I think our interpretation has much to do with Luke 22:19-20:
19 And he took bread, gave thanks and broke it, and gave it to them, saying, "This is my body given for you; do this in remembrance of me." 20 In the same way, after the supper he took the cup, saying, "This cup is the new covenant in my blood, which is poured out for you."
In fact, on the face of our own church's altar, before which the Supper is administered, it is literally chiseled "Do This In Remembrance Of Me". I understand "our" argument that Jesus was instituting a fundamental and extremely important remembrance through symbolism. The Bible is replete with symbols and reminders for us. He knows how dumb we are, and He's right! :) I suppose I just don't understand the "level" of literalness that Catholics believe, since no credible person argues that the disciples actually ate of His flesh and drank of His blood. The passage does not support that at all anyway, they were breaking bread.
This is not intended as a "we are better than you are" measure. Rather it is intended to ensure that those taking the sacrament do not do so unworthily and thereby bring judgment upon themselves. Scripture expressly warns that taking the body and blood unworthily can be to your judgment.
We also urge caution to the extent that nonbelievers should not take the Lord's Supper in our church. I don't know those verses, but I would imagine that our respective churches would quote similar scripture. I wonder if there is a difference for a hypocrite vs. an unknowing violator.
"I suppose I just don't understand the "level" of literalness that Catholics believe, since no credible person argues that the disciples actually ate of His flesh and drank of His blood."
300,000,000 Orthodox Christians believe exactly that, as did all Christians until the Reformation.
I think Forest Keeper means (correct if I'm wrong) that no person standing there while Christ spoke at John 6, bit off a bit of His flesh and drank his blood. In which case he'd be correct. :)
As one in an interfaith marriage to a Catholic, I will not say I don't have a problem with the determination of the Church that a confirmed and baptized Protestant like myself is not allowed to participate in the sacrament in their Church because I don't share their beliefs about the nature of the host. I know many Catholics who do not literally believe in transsubstantiation, who even state openly that they do not, but the Church does not bar them from the sacrament.
I do respect the wishes of the Church, in that I do not take communion in their Church. But I do not think many in the Church would be pleased to hear the answer I have for my daughter when she, inevitably, asks why I am not taking communion.
To expound on the nature of the elements, between the Roman Catholic view and the Baptist view, there are two additional positions. The Lutheran view is quite close to the RC view. It holds that the body and blood are really physically present, without the bread and wine losing their identity as such. The Reformed view is that there is a real, but spiritual rather than physical, presence in the bread and wine or grape juice.