Probably one of the most fun part of the new Pottermore is wand shopping. The process of choosing a wand (or letting a wand choose you) is actually a quiz that's kind of like Kokology. People are usually happy with their wands (unlike their sorted houses) and they're usually very accurate. It's fun to learn more about the different kinds of wood and wand core and how your wand matches your personality very well. I'll share with you Mr. Ollivander's thoughts about the characteristics of my wand:
HornbeamMy own wand is made of hornbeam, and so it is with all due modesty that I state that hornbeam selects for its life mate the talented witch or wizard with a single, pure passion, which some might call obsession (though I prefer the term ‘vision’), which will almost always be realised. Hornbeam wands adapt more quickly than almost any other to their owner’s style of magic, and will become so personalised, so quickly, that other people will find them extremely difficult to use even for the most simple of spells. Hornbeam wands likewise absorb their owner’s code of honour, whatever that might be, and will refuse to perform acts - whether for good or ill - that do not tally with their master’s principles. A particularly fine-tuned and sentient wand.
Dragon
As a rule, dragon heartstrings produce wands with the most power, and which are capable of the most flamboyant spells. Dragon wands tend to learn more quickly than other types. While they can change allegiance if won from their original master, they always bond strongly with the current owner.
The dragon wand tends to be easiest to turn to the Dark Arts, though it will not incline that way of its own accord. It is also the most prone of the three cores to accidents, being somewhat temperamental.
As for wand flexibility and length...
Many wandmakers simply match the wand length to the size of the witch or wizard who will use it, but this is a crude measure, and fails to take into account many other, important considerations. In my experience, longer wands might suit taller wizards, but they tend to be drawn to bigger personalities, and those of a more spacious and dramatic style of magic. Neater wands favour more elegant and refined spell-casting. However, no single aspect of wand composition should be considered in isolation of all the others, and the type of wood, the core and the flexibility may either counterbalance or enhance the attributes of the wand’s length.
Most wands will be in the range of between nine and fourteen inches. While I have sold extremely short wands (eight inches and under) and very long wands (over fifteen inches), these are exceptionally rare. In the latter case, a physical peculiarity demanded the excessive wand length. However, abnormally short wands usually select those in whose character something is lacking, rather than because they are physically undersized (many small witches and wizards are chosen by longer wands).
Wand flexibility or rigidity denotes the degree of adaptability and willingness to change possessed by the wand-and-owner pair - although, again, this factor ought not to be considered separately from the wand wood, core and length, nor of the owner’s life experience and style of magic, all of which will combine to make the wand in question unique.