Edit in JSFiddle

<input type='text' name='input' value='' placeholder='Текст нашего placeholder'>

input::-webkit-input-placeholder{
    color: red;   
    font-style: italic;
    font-weight: bold;
}
input:-moz-placeholder{
    color: red;   
    font-style: italic;
    font-weight: bold;
}
input{
    width: 250px;
    color: blue;
    font-weight: normal;
    font-style: normal;
}