Was it Oblivion that was rerated M due to the mods available on the PC(but the XBOX didn't have it as a problem)?? Thought it was odd that a game have it's rating adjusted based on mods that were only available on one platform.
No. The mod got it re-evaluated, but the reason it was bumped up to "M" was someone actually played the Dark Brotherhood questline the second time around.
"It's a fine day with you around" is said many females NPCs (even towards female PCs), as is "Don't be a stranger"
Also,
Spoiler Kematu of the Alik'r is under the impression that Saadia seduces a Male PC into helping her (don't know about female, but it's very possible considering the above)
There's absolutely nothing sixual about either of those phrases... Some people see weird stuff in the most innocent of things.
The books and Dibella have all the "sixual Themes" needed to get that listed on the ESRB rating.