To anyone who is sick of this my apologies.
My comments below are added for doctrinal clarity only...

They MOST CERTAINLY heard the Gospel of Christ:
The entire chapter is filled with the death, burial and resurrection of Christ.
They are preaching Christ crucified.

ACTS 2 (subheads are mine)

NOTE THE REVELATION OF JESUS
22 Ye men of Israel, hear these words; Jesus of Nazareth, a man approved of God among you by miracles and wonders and signs, which God did by him in the midst of you, as ye yourselves also know:

NOTE THE DEATH OF CHRIST (CHRIST CRUCIFIED)
23 Him, being delivered by the determinate counsel and foreknowledge of God, ye have taken, and by wicked hands have crucified and slain:

NOTE THE RESURRECTION OF CHRIST
24 Whom God hath raised up, having loosed the pains of death: because it was not possible that he should be holden of it.

25 For David speaketh concerning him, I foresaw the Lord always before my face, for he is on my right hand, that I should not be moved:

26 Therefore did my heart rejoice, and my tongue was glad; moreover also my flesh shall rest in hope:

27 Because thou wilt not leave my soul in hell, neither wilt thou suffer thine Holy One to see corruption.

28 Thou hast made known to me the ways of life; thou shalt make me full of joy with thy countenance.

29 Men and brethren, let me freely speak unto you of the patriarch David, that he is both dead and buried, and his sepulchre is with us unto this day.

AGAIN, NOTE THE RESURRECTION OF CHRIST
30 Therefore being a prophet, and knowing that God had sworn with an oath to him, that of the fruit of his loins, according to the flesh, he would raise up Christ to sit on his throne;

DEATH AND BURIAL OF CHRIST
31 He seeing this before spake of the resurrection of Christ, that his soul was not left in hell, neither his flesh did see corruption.

NOTE THE RESURRECTION OF CHRIST
32 This Jesus hath God raised up, whereof we all are witnesses.

NOTE AGAIN CHRIST CRUCIFIED
36 Therefore let all the house of Israel know assuredly, that God hath made the same Jesus, whom ye have crucified, both Lord and Christ.

NOTICE THEY CLEARLY HEARD THE MESSAGE:
37 Now when they heard this, they were pricked in their heart, and said unto Peter and to the rest of the apostles, Men and brethren, what shall we do?

BAPTISM IN THE NAME OF JESUS CHRIST
38 Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.

39 For the promise is unto you, and to your children, and to all that are afar off, even as many as the LORD our God shall call.

40 And with many other words did he testify and exhort, saying, Save yourselves from this untoward generation.

BELIEVER'S BAPTISM FOLLOWS AFTER THEY RECEIVE THE WORD
41 Then they that gladly received his word were baptized: and the same day there were added unto them about three thousand souls.

So we can clearly see that they most certainly HEARD AND RECEIVED the Gospel of Christ, as defined in I Corinthians 15:1-4, where Paul is reminding the church at Corinth:

"Moreover, brethren, I declare unto you THE GOSPEL which I preached to you, which also you received, and in which you stand; by which also you are saved, if you hold fast that word I preached to you, unless you believed in vain. For I delivered to you first of all that which I also received; that Christ died for our sins according to the scriptures, and that He was buried, and that He rose again the third day according to the scriptures."