Yeah, there's no way the producers will announce a new Bond until well after B25 has been released. For now, beware any hype you see about this or that young actor being touted as the new Bond. Such "rumours" mostly emanate from British bookies and teams of publicists and agents.
B25 has been a troubled production. The film's original director, Danny Boyle, left over "creative differences" with Craig and the producers. There have been three or four other writers in addition to Purvis & Wade working on it, too. By the time it comes out it'll be almost five years since Spectre, much of which I quite liked up until the final thirty minutes or so.
Skyfall really is superb, one of the most beautifully shot films I've ever seen. And I particularly like the Bond-girl baddie, Berenice Marlohe, who has an elegant if somewhat creepy sexuality like few others in the series, a true femme fatale:
https://youtu.be/kVz7ELEQMuc
Live and Let Die & Diamonds are Forever are my favorite title tunes; but any of the scores by John Barry are truly outstanding, especially the one for OHMSS:
https://youtu.be/jcQQjvQRqCU