It's a bit of an odd film. Basically, it's created in part by a complicated issue over the authorship of Thunderball-basically, Fleming and another writer originally planned it as a film script featuring Bond. However, Fleming later turned the concept into a novel, and the novel was the first to introduce SPECTRE and Blofeld. (Whereas the films didn't adapt TB until the fourth film, so they were both introduced earlier in Dr.No and From Russia With Love, with SMERSH being the original bad guys in the books). However the co-writer, Kevin McClory-got upset at this, and demanded partial credit for Thunderball, as well as the rights to SPECTRE and Blofeld (Hence them not appearing in the main series for many years, apart from a sort-of cameo in FOR YOUR EYES ONLY which really only used the bald head and cat, both trademarks mainly of the film Blofeld; although the cat does appear in NSNA). Eventually, NSNA was the result of McCory flexing those rights.
It's a bit odd. There's no Bond theme whatsoever, the main titles are played over the action instead of being they're own thing, no gunbarrel, (there's an 007 that sort of tries for the affect though). M, Q and Moneypenny are somewhat even more caricatured, etc. However, it did anticipate some parts of the film series (Such as Bond being put out to pasture, and the gadgets are very similar to GOLDENEYE, black Felix). Connery also seems to be having a lot more fun, and is more fit despite being a dozen years older, than in DIAMONDS ARE FOREVER. Plus Klaus Maria Schneider as Largo is a lot more scary and crazy than Adolfo Celfi's version. Basinger's kind of iffy but Barbera Carerra is a lot of fun as Fatima Blush, who is basically Fiona Vulpe from Thunderball but turned up to 11.