try this:
$itemsVisible = Mage::getSingleton('checkout/session')->getQuote()->getAllVisibleItems();
foreach($itemsVisible as $item) {
$product = $item->getProduct();
$attrs = $product->getTypeInstance(true)->getConfigurableAttributesAsArray($product);
foreach($attrs as $attr) {
if(0 == strcmp("color", $attr['attribute_code'])) {
$options = $attr['values'];
foreach($options as $option) {
print "{$option['store_label']}<br />";
}
}
if(0 == strcmp("size", $attr['attribute_code'])) {
$options = $attr['values'];
foreach($options as $option) {
print "{$option['store_label']}<br />";
}
}
}
}
OR
$itemsVisible = Mage::getSingleton('checkout/session')->getQuote()->getAllVisibleItems();
foreach($itemsVisible as $item) {
$product = $item->getProduct();
$attributes = $product->getTypeInstance(true)->getSelectedAttributesInfo($product);
foreach($attributes as $attr) {
if(0 == strcmp("color", $attr['attribute_code'])) {
$options = $attr['values'];
foreach($options as $option) {
print "{$option['store_label']}<br />";
}
}
if(0 == strcmp("size", $attr['attribute_code'])) {
$options = $attr['values'];
foreach($options as $option) {
print "{$option['store_label']}<br />";
}
}
}
}