With a bit of humiliation I will admit, this will probably be my favorite romance anime for a while.
There are other anime classified as romance that I hold in high regard, but in those cases I usually like them because of various other elements, mostly fantasy, more rarely comedy. For example, AIR is still my all-time favorite anime, but AIR had a lot of fantasy elements that I consider AIR more of a favorite fantasy type anime than a romance (plainly I couldn't see any romance getting past Misuzu and Yukito being brother and sister, anyway).
Similary ef-tales of memories had some fantastical elements, but they were not abstractly connected to reality. Instead, the show had a ton of symbolism. A RIDICULOUS AMOUNT THAT CAUSED ME TO RESURFACE MY TENDENCIES TO POINT OUT SUCH SYMBOLS... the broken leg, the sheep math problem, and ultimately, the novel written by the andrograde amnesia girl. I really could not help but say "that is just neat" everytime they included such symbolic elements, even though the world around them is still very much similar to a regular, realistic world.
(Save for some points that they never went into, which is a bit bothersome but serves the purpose of emphasizing that this is a romance anime.)
Those symbolic points, along with the andrograde amnesia case which I have to find interesting since I take biology and neurology courses, are the main aspects that set this anime apart from other romance anime. Other romance anime typically emphasize so much on lovey-dovey that it becomes boring to me to continuously watch it; this one had, first, the memory-deficient girl which has the audience (aka me) saying "interesting", then continues to add various symbolic meanings and drawings as the series goes on. It's sad to say that it's one of those anime I can't watch one time to catch all the symbolism and meanings, yet don't feel like watching it all over again... I might anyway.
The only anime I have done that with right now is AIR.
That being put aside, I've decided to list my favorite anime in each anime genre.
Romance: ef-tales of memories
Comedy: Nodame Cantabile (I watch a lot of comedy just for laughs, but since it is comedy, it never really strikes out as "this is incredible" or "this is so touching"... Nodame Cantabile is quite decent however)
Fantasy: AIR
Action: Magical Lyrical Girl Nanoha
Science Fiction: Stellvia of the Universe (old favorites die hard?)
Slice of Life: Aria
Suspense: Code Geass (Good anime but &^*&^$*#^ stupid cliffhangers)
Other series worth noting that I haven't noted because I've been too busy watching anime:
Sayanora Zetsubou Sensei: A sarcastic comedy anime. Fun to watch but kind of leaves you feeling like "wtf" for some time. Many people say the art design for this anime rocks. I agree.
Gurren Laagan: A mech anime introduced to me by a friend. If I were to define mech anime, I'd use this anime as the example, just like if I were to define utopia I'd use Aria.
Sky Girls TV: I like this anime's art style, but I haven't watched enough to say much about it. So far it's slow, but I'm liking it.
I've watched a lot of anime and wanted to write stuff up on it, but because of my laziness I haven't done much. And now school is going to start soon. Oh well, it was a fun anime-filled winter break for me...~