I'd say he's a bit more popular.  Aquaman has seemed to be able to maintain a solo book better than Namor has in the last 50 years.  

Actually, Aquaman's popularity soared past Sub Mariner's. Take a look beyond comics: in the 60s, while Sub-Mariner had his Marvel Superheroes segments shared with four other characters, Aquaman had a full animated TV series of his own, and years later, being one of the few DC characters to be featured in every season of The Super-Friends from 1973-1985.

He also had greater merchandising pull, such as a 1960s board game, Big Little Book, being one of Ideal's Captain Action figure costumes, and other toys. In the 70s, Aquaman was popular enough to warrant his own Mego 8-inch action figure (in fact, he was one of the original quartet of characters produced) and later in the decade, a 3 3/4 inch figure, glassware, children's records, clothing, school stationary, Halloween costumes, etc., while I believe Sub-Mariner's most high profile merchandising in that era was an appearance on a poster, t-shirt, Topps' Marvel Super Heroes trading cards, and one of 7-11's Slurpee cups. 

Whether one thinks of comic characters as something exclusively for kids, or something for all ages, it sort of says something when Aquaman was so heavily marketed, especially to the general public, but Sub Mariner was not. 

Jump to this century, and Aquaman has had regular appearances on two Justice League cartoons, Smallville (and a spin-off pilot), the Justice League movie and now, he already has his solo movie set for release. On the other side of the street, I recall Stan Lee talking about wanting to develop a Sub Mariner TV series in the late 70s/early 80s, which obviously never materialized, and ever since that time, the character has been bounced from one studio and/or producer to another in constant development hell. 

Aquaman's sitting pretty high compared to Namor.

My post above doesn't say "yeards", and the post wasn't edited. How did it get into the quote?

Sorry for seemingly forgetting about this thread. I got strep throat the day after I posted this and it slipped my mind. Ugh.

As I crawl my way through my Marvel Age reading project (finished ASM #13 yesterday) I'm really looking forward to reading the Sub-Mariner solo series. I've read all of the Tales to Astonish strips back when I did a huge Hulk reading years ago but I've never had the opportunity to read the original series. I was a huge fan of Byrne's 90's series and got in on that as soon as it was released.

I have a question that I'm sure has been asked many times before: did Namor influence the original designers of Star Trek when formulating the appearance of Spock and the other Vulcans? I'd rather ask here because, as we know, there are a lot of jive fact out there on the interwebs, particularly when it comes to Star Trek lore.

My two cents, echoing some of what he's been said before:

1) Namor's appearance is off-putting. Weird shaped head. Tiny bird wings on his feet (presumably a design element borrowed from Mercury's boots) that make no sense for an underwater character. The speedo is both too little clothing for a male hero, and yet too much for an underwater character. I remember seeing Alex' Ross nude Namor show up in Marvels and thinking, "Yes, that's what he would actually be like."

2) Alien setting. Not only is it unfamiliar, but it doesn't seem as well developed as, say, Thor's Asgard. I can tell you all about the interesting ways that Odin and Loki and Karnilla and Lorelei and the Enchantress and Hela and the Frost Giants mess with each other. Lots of factions, lots of story opportunities. There just doesn't seem to be a lot going on under the sea besides monsters and occasional palace betrayals.

3) Lack of positive relationships. I can tell you all about what Kitty Pryde thinks respectively of Colossus, Nightcrawler, Wolverine, Storm, Cyclops, and Professor X as individuals. I can tell you what Batman thinks of Superman, Green Arrow, and Wonder Woman. With Namor all that comes to mind is, "I hate everyone on the surface. Except Sue Storm. I will cuckold her husband whenever I can." Byrne tried to connect Marrina with Namor, but that move wasn't supported by subsequent authors, as far as I know. When no one in the story really likes a given character, readers tend not to like him either. That's why writers know to give an unlikeable character a pet or a child, someone who can be shown having positive, loving interactions. Even the Namor-Sue relationship seems to be more about desire than affection.

I think a good bit of the lack of recognition has to do with the fact that he's perceived as an Aquaman knock-off and with Aquaman's name already being dragged through the mud due to the notion that his only power is talking to fish....