The robots are looking even shinier.Actual weekend gross for DreamWorks and Paramount’s “Transformers” was $70.9 million, versus Sunday’s estimate of $67.6 million, a gain of 4%. That pushes the 6½ day opening cume to $155.4 million, 2% ahead of the $152.5 million estimate. It’s the biggest seven day opening on the books for a non-sequel, besting record-holder “Spider-Man,” which made $151.6 million in its first seven days. Actual returns also upped the pic’s overseas take. “Transformers” weekend total was $46.7 million, a 7% gain over the estimated $43.6 million reported Sunday. Tentpole’s international cume is $96.7 million for a worldwide total of $252.5 million.