Cartoon Brew offers some screenshots from the upcoming Looney Tunes Golden Collection Volume 2, including title cards from several cartoons that have had their original opening titles restored. Like most studios, Warner Brothers periodically reissued their old cartoons; but when they did so, they removed the opening titles and music and substituted a generic opening sequence with just the title, no credits, and only the "Merrie Melodies" theme music. (The only cartoons that didn't usually get this treatment on reissue were Bugs Bunny cartoons, which were usually reissued intact and therefore survive with complete credits and music.) Four cartoons on the new DVD have been restored with their original titles, but several others remain credits-less, because WB (like most studios) cut the new titles into the original negatives upon reissue.
This was the "Blue Ribbon" series, so called because the sequence contained a blue ribbon and a statue that looked sort of like, but wasn't, an Oscar. I believe this was done in response to studios like MGM, whose reissues of Oscar-winning cartoons would revise the title sequences to boast of the award win. At the time they started reissuing cartoons, WB had no Academy Awards for best short cartoon (undeservedly, I think most of us would agree; the Academy didn't seem to acknowledge the existence of any cartoon studio outside of Disney and MGM), so they came up with this "Blue Ribbon" thing to make it look like they were reissuing award-winners. As for the removal of the credits, I've heard it speculated that that might have been part of WB's policy of not crediting artists who had left the studio (e.g. after Bob Clampett left, the cartoons he was working on at the time of his departure were released without a director credit). The policy finally changed around 1956, and the "Blue Ribbon" reissues after that (of cartoons dating from 1949 onwards) had full opening titles and music.
Fortunately the four restored-credits cartoons (all the cartoons are "restored" from the original negatives, but those are the four that will have credit sequences we haven't seen before) on the new set are all genuine classics: Tex Avery's "I Love To Singa," Bob Clampett's "Baby Bottleneck" and "Book Revue," and Friz Freleng's "Back Alley Oproar." A couple of other cartoons, the edu-toon "Old Glory" and Frank Tashlin's "Have You Got Any Castles," remain Blue Ribbon but have some material restored that was cut from the reissue prints.