I just finished listening to the whole album, and I have to say...
Hold it Against Me is the best song on the album, it's her best song in YEARS, it's on the level of her best songs. The production is so perfect, it has no defined pre-chorus or chorus, the breakdown is

, and how the song gains that strength towards the end. It's so perfect.
IMO it's among Britney's best singles EVER. It's in my Top 5.