well the random card generators they say they use should mean that every deal should be completely random in an online game (of course we could get into the whole issue of how some of the sites use 'tweaked' software to create more action flops and thus more rake, but we won't even go there)
In live games, the deals should be random aswell, but of course there is the factor of non-perfect shuffles that leave some cards closer to others, and therefor deals are not completely random.
Basically, omitting some tiny %ages, the deals should be completely the same in online and brick and mortar games.
EDIT: i see only now that you are talking about odds of hands (i should read the posts more thoroughly )
The odds are exactly the same.
As SexyAceJoker said, many people chase hands more, and therefore you see made hands more (flushes, straights, etc) which you might not see as often in live games.
Also the fact that you play something like 10X faster online brings the long-term to short-term, and you see alot more hands at the showdown due to this. This does not mean that the % is higher, just the # of them in a set amount of time which makes it seem so.