Hi Criss,,
Short answer: Some consider Laamastum to mean actual sexual intercourse, others intimate touching and others that it is simply touching.
Here is a longer explanation:
7. Touching Women[22]
The scholars differed over whether the touching of a woman nullifies wudu`.
In the Shafi’ee madh-hab[23] the wudu` of a man is nullified if he touches a woman, without a barrier, with his hand or otherwise, regardless of whether she is attractive or not, Muslim or non-Muslim, except a mahram[24] (by blood, nursing or marriage).
In the Maalikee madh-hab, touching of women nullifies the wudu` of the toucher and the touched if the following conditions are met[25]:
The toucher has reached puberty
The subject of the touch is one of the nature from which pleasure is usually derived; even if she is not of age and even if the touch occurs by a nail or hair, or with/without a barrier
The toucher intends or feels pleasure while touching
In the Hanafee madh-hab, the touching of a woman, even with desire, does not nullify the wudu`. They consider the words “laamastum” to refer to intercourse.
The favored opinion of the author, that of the Hanbalees, is as follows: (the type of touching that would nullify the wudu` is that which fulfills the following criteria)
The touch is sensual (arousing sexual feelings)
Regardless of who is touched (i.e. male touching female or vice verse, or even of the same sex, young or old person, mahram or non-mahram, etc.)
Regardless of whether or not a barrier is present (i.e. skin to skin or over clothing)
Both the one touching and the touched would have their wudu` nullified if they derived pleasure from the touch
Evidence for the correctness of this view:
Aisha narrated that the Messenger of Allah (peace be upon him) would kiss one of his wives, then he would go out to perform salah and would not renew his wudu`. This hadith indicates that touching of the woman doesn’t nullify the wudu`.
Narrated ‘Aisha: “I used to sleep in front of Allah’s Apostle with my legs opposite his Qibla (facing him); and whenever he prostrated, he pushed my feet and I withdrew them and whenever he stood, I stretched them.” ‘Aisha added, “In those days there were no lamps in the houses.” If touching a woman would nullify the wudu`, then the Prophet (peace be upon) would not have touched his wife and then continue praying. There are many other reports that substantiate this claim.
http://deenesteem.wordpress.com/2010/08/16/fiqh-tahaarah-p5/