The majority of your starting ranks in the Common Skills are determined by your choice of culture. This provides insight into what professions each of the cultures prizes, as well as what types of opportunities might be available within a culture. Mechanically, it helps make the cultures more distinctive. There's obviously still room for customization since you get your "previous experiences" points that you can spend however you want, and as you gain advancement points you'll obviously spend those to upgrade the skills that are important to you. Specifically, each culture's skill point "value" is 29 (based on the previous experience skill point table) and you get 10 "previous experience" skill points to spend as you see fit. So when you first create your character, roughly 3/4 of your skill points are pre-selected. At first I didn't like this ratio since I value customization, but I get why the designers went this route now, and I might actually prefer it this way the more I think about it. It says a lot about what life is like for an individual of a given culture, and customization is gained through adventuring.
Anyways, the point of this post is to provide a quick reference. While the skill rank table works very well for building characters, a list would be more helpful for finding out what each culture does well at a glance. Here is that list. Key to the skill groups is as follows: Personality, Movement, Perception, Survival, Custom, Vocation.
3 Ranks: Persuade
2 Ranks: Inspire, Travel, Insight, Explore, Courtesy, Battle
1 Rank: Awe, Search, Song, Craft, Lore
0 Ranks: Athletics, Stealth, Awareness, Healing, Hunting, Riddle
Bardings tend to be well-rounded with a large amount of skills with 2 or 1 rank(s), which maximizes total number of skills. They have the fewest 0 rank skills of any other culture. This opens up a lot of different options, giving individual Bardings a good starting point to specialize in a wide variety of areas. Given their privileged society, and good relations with both the Dwarves and Elves, this makes sense. Their specialty is their persuasiveness. They tend to excel best in the Personality group, with solid marks in Vocation as well. Weaknesses are Movement and Survival (which, interestingly, are strong points for the other generalist culture, the Woodmen).
3 Ranks: Awe, Insight, Hunting
2 Ranks: Athletics, Awareness
1 Rank: Inspire, Search, Healing, Riddle, Craft
0 Ranks: Persuade, Travel, Stealth, Explore, Song, Courtesy, Battle, Lore
Beornings tend toward a deep focus in some skills with modest investment (1 rank) in a decent amount as well (if graphed they would have 2 large peaks at either end, having a lot of rank 3 and rank 1 skills). They are above all imposing, discerning, and remarkable hunters. They place little value on Custom and Vocation skills, and surprisingly Movement, though to a lesser extent. No ranks in Battle is very surprising given their way of life (personally I'd be tempted to house-rule a trade between Battle and Inspire). Perception is their strongest group.
Dwarves of the Lonely Mountain
3 Ranks: Travel, Search, Craft
2 Ranks: Inspire, Explore, Riddle
1 Rank: Song, Battle
0 Ranks: Awe, Persuade, Athletics, Stealth, Awareness, Insight, Healing, Hunting, Courtesy, Lore
They are the most focused of the cultures, and it fits. They lean the most toward maximizing ranks, meaning that they specialize in fewer areas but are very talented in those areas. Consequently, they have the greatest number of 0 rank skills. Despite this they're surprisingly well-rounded, with a focus (rank of 2 or 3) in 1 skill from each of the groups. They're best known for their craft, resilience to discomfort, and obsessive ability to find what they're looking for (or a stubbornness that keeps them from giving up). Some of the skills that they ignore are very surprising given the source material, namely Insight and Courtesy but you could make an argument for Lore as well.
Elves of Mirkwood
3 Ranks: Athletics, Lore
2 Ranks: Awe, Stealth, Awareness, Song, Battle
1 Rank: Healing, Hunting
0 Ranks: Inspire, Persuade, Travel, Insight, Search, Explore, Courtesy, Riddle, Craft
The Elves are unparalleled in their ability to collect (and recall) Lore, and given their tough, immortal bodies it's not surprising that they are capable of great athleticism. Their rank 2 list all fit perfectly with what we know about Elves. They're surprisingly deficient in the Survival category (considering they're wood-elves); I would think they'd get at least a rank 2 in Hunting, and perhaps a rank 1 in Explore. Their haughtiness and inability to relate with mortals can easily explain the lack of focus in Personality, Perception, and Custom groups (with the obvious exceptions of Awe, Awareness, and Song).
Hobbits of the Shire
3 Ranks: Stealth, Courtesy
2 Ranks: Persuade, Awareness, Search, Song, Riddle
1 Rank: Travel, Insight
0 Ranks: Awe, Inspire, Athletics, Explore, Healing, Hunting, Craft, Battle, Lore
Stealth and Courtesy are perfect for the Hobbits main areas of expertise. Overall they're very well-represented in the Custom and Perception groups. They're arguably the most polarized culture, however, since they have no ranks in any skills from the Survival or Vocation group. Everything seems to fit really well with what you'd expect from a Hobbit.
3 Ranks: Explore, Healing
2 Ranks: Athletics, Stealth, Awareness, Hunting
1 Rank: Inspire, Song, Riddle, Craft, Battle
0 Ranks: Awe, Persuade, Travel, Insight, Search, Courtesy, Lore
Not surprisingly, Woodmen have a heavy focus on the Survival group, with strong showings in Movement as well. Overall they're really well-rounded, as only Bardings have fewer skills with 0 Ranks. Like Bardings, they seem to strive for competence in as many areas as possible (tendency toward many rank 1 and 2 skills). This makes sense given their lifestyle and frugal standard of living; without a formalized division of labor and with scattered settlements, each individual Woodman needs to be able to perform a wide variety of tasks. Personality is their worst group, with a weak showing in Perception as well (with the exception of Awareness).