sounds like liquid drum and bass to me. the channel of the 1st video (liquicity) is an excellent source for more groups of similar sounds.
off the top of my head, here are a few recommendations: netsky, rollz, loadstar, fred v and grafix (a personal favorite), maduk, feint, rameses b, sulex, two thirds (another favorite). id start with netsky as hes by far the most popular and you should be able to find lots of his tracks on youtube pretty easily, some of the groups iv listed are a bit obscure.
other drum and bass (not liquid) which is also recommended: high contrast (his last album "The Agony & The Ecstasy" is a masterpiece imo), chase and status, black sun empire.
hope this helps