WordPress CSV importer upload form

wp_csv_import.php

<h3><?php echo __('Upload CSV'); ?></h3>

<form action="" method="post" enctype="multipart/form-data">

    <tr>
        <td width="20%"><?php echo __('Select file'); ?></td>
        <td width="80%"><input type="file" name="file" id="file"/></td>
    </tr>

    <tr>
        <td>Submit</td>
        <td><input type="submit" name="submit"/></td>
    </tr>

</form>
<?php
if ($_FILES) {
    // Get the type of the uploaded file. This is returned as "type/extension"
    $arr_file_type      = wp_check_filetype($_FILES['file']['tmp_name']);
    $uploaded_file_type = $arr_file_type['type'];

    // Set an array containing a list of acceptable formats
    $csv_file_types = array('text/csv', 'text/plain', 'application/csv');
    if (!function_exists('wp_handle_upload')) {
        require_once(ABSPATH . 'wp-admin/includes/file.php');
    }

    $uploadedfile = $_FILES['file'];
    if ($_FILES['file']['type'] !== 'text/csv'){
        echo '<pre>ERROR, Only upload files in the CSV format!</pre>';
    }
    else {
    $upload_overrides = array('test_form' => false);

    $movefile  = wp_handle_upload($uploadedfile, $upload_overrides);

    echo '<pre>';
    if ($movefile) {
        echo "File is valid, and was successfully uploaded.\n";
        var_dump($movefile);
    } else {
        echo "ERROR, file was NOT uploaded!\n";
    }

    if (!file_exists($movefile['file']) || !is_readable($movefile['file'])) {
        return false;
    }
    $header = null;
    $data   = array();
    # Open the File.
    if (($handle = fopen($movefile['file'], "r")) !== false) {

        while (($row = fgetcsv($handle, 1000, ",")) !== false) {
            if (!$header) {
                $header = $row;
            } else {
                $data[] = array_combine($header, $row);
            }
        }
        fclose($handle);
    }
    $new_post_ids = $this->add_posts_from_csv_data($data);

    echo '</pre>';
}
} //end else of file type check

This works well. However, I have a couple of suggestions:

Add application/vnd.ms-excel to $csv_file_types = array('text/csv', 'text/plain', 'application/csv');

$csv_file_types = array('text/csv', 'text/plain', 'application/csv', 'application/vnd.ms-excel');

Change if ($_FILES['file']['type'] !== 'text/csv') to if (!in_array($_FILES['file']['type'],$csv_file_types)) so that it reads all file types in the $csv_file_types array.