The short answer seems to be '...Kinda' You will lose some functionality of the xbee itself.
However, below is what you lose(I think).
All of which seems to be things that an UNO or Mega can handle.
#126 seems to provide the connections to use the xbee as a wireless serial connection,
figuring you will use your Arduino product to do this work (and provide flow control, etc).
There's probably a few others as well, for instance, they hack their own product here: http://www.ladyada.net/make/xbee/arduino.html
To set up allow you to reset your arduino wirelessly...
From the Xbee Manual:
Pin functions and their associated pin numbers and commands
AD = Analog‐to‐Digital Converter, DIO = Digital Input/Output
Pin functions not applicable to this section are denoted within (parenthesis).
Pin Function Pin# AT Command
AD0 / DIO0 20 D0
AD1 / DIO1 19 D1
AD2 / DIO2 18 D2
AD3 / DIO3 / (COORD_SEL) 17 D3
AD4 / DIO4 11 D4
AD5 / DIO5 / (ASSOCIATE) 15 D5
DIO6 / (RTS) 16 D6
DIO7 / (CTS) 12 D7
DI8 / (DTR) / (Sleep_RQ) 9 D8