Yes, in Bluetooth Smart (formerly known as Bluetooth Low Energy) its the GATT(Generic Attribute ) Profile that is responsible for service discovery, see this article on GATT and the ATT protocol.
Quoted from the article:
Since GATT puts all service details on
ATT, there is no need for a separate
service discovery protocol (SDP),
like we have in BR/EDR. The ATT
protocol is used for everything:
disconvering services, finding
services' characteristics,
reading/writing values, and so on.
