I just saw Let the Right One in last night, as it happens. Although I liked it, it didn’t live up to the fulsome praise I’ve seen for it here and elsewhere, IMHO. The remake trailer looks good and I’m sure I’ll see it, too.
As to the young vampire’s secret:
[spoiler]I noticed the scar when Eli was putting on the borrowed dress, but actually thought (crazy and weird, I know, but what the hell, this is a movie about a vampire) that it might be a horizontal vagina. I don’t think Eli’s long-previous castration is a vital plot point, and wouldn’t terribly mind if it were omitted from the American remake.
For that matter, Wiki says that in the book, Eli’s “dad” or blood procurer is actually a pedophile who wants to have an affair with her; this was entirely omitted from the original movie, without harming the film, I’d say.[/spoiler]