As an attendee of Smith College as an undergrad within the past 5 years, I can attest to its excellece. While not for everyone (you have to know you want to be around all women, duh), it rewards those 2,800 or so who come back every fall.
The classes are demanding, prepare for a miniscule social life. If you wish you can slack off, but finals come and you'll find there is only so much you can get away with. The option to take classes at the other 5 colleges is great, even though it takes effort.
Profs are not distant and make an effort to be acsessable. The campus is beautiful, for undergrads and visitors. Come for the fall Mum show or spring bulb show at the greenhouse. The newly remodeled art museum has great modern works, and free on the first saturday of the month.