Yah, there is a perk that increase XP earned, but if you think about it increasing XP by 10% is an almost criminal waste of a perk.
An example: In Fallout 3 the level 2 perks are:
Black Widow/Lady Killer - Special speech options and +10% damage to opposite six
Daddy's Girl/Boy - +5 Science, + 5 Medicine
Gun Nut - +5 small guns, +5 repair
Little Leaguer - +5 Melee, +5 explosives
Thief - +5 sneak, +5 lockpick
Intense Training - permanent increase of a SPECIAL stat by +1
and Swift Learner - +10% XP
You only get so many perks. in Fallout 3 you get one perk per level, In New Vegas you get one perk every TWO levels. That gives you a total of 30 standard perks for Fallout 3 and 25 standard perks for New Vegas
Out of that list the best two Perks is the Black Widow/Lady Killer Perks and the Intense Training perk. If you are a high intelligence player, these two perks are the only ones you should ever take from the level 2 perk list.
The Swift Learner perk only grants you a slightly faster leveling rate but nothing else. Essentially, you can make high level quicker but you have lost one perk that could have been used for an increase in power.
Depending on the build for your character the others may or may not be useful. The more Intelligence you have, the less useful they will be. (The amount of skill points you gain per level is 10 + Intelligence in Fallout 3). A low intelligence player will never be able to max all skills, but with careful selection of the +skill perks they an max one, be decent in one or two more and still get pretty good in sneak, lockpick and medicine or speech.
In my opinion Swift Leaner falls in with Perks like Here and Now, basically I think of it as throwing away a perfectly good perk.