I just posted this comment in another thread but it is relevant here also. If you are replacing floorstanders you basicaly have three options, a pair of the bookshelf speakers like the X-LS Encores or the larger X-CS Encores (3 driver MTM version of the X-LS intended for use as a center channel but also great as left and right main speakers) or the X-MTM Encores which are X-CS Encores in a full length cabinet but may be too large for your room.
The X-LS or X-CS Encores would need speaker stands. The speaker/stand combination doesn't take up any more floor space than the towers do and the cost of the extra wood is usually cheaper than the cost of a good pair of stands. Going with the floorstanding version would give you a lot more bass extension than either of the smaller cabinets would.
Unless you decided to put a pair of the X-LS or X-CS Encores on a pair of Danny's Best Speaker Stand Ever. Now that would be one heck of a combo.
http://www.audiocircle.com/index.php?topic=129161.0 Here's a couple of pics Danny posted in his thread:


Using these as stands will relieve any worries about not having enough bass in the system
You also might want to give serious consideration to Danny's newest design, the Skinny 6
http://www.audiocircle.com/index.php?topic=135458.0 Here's a couple of pics of them from Danny's thread:


Yes they are towers but the pictures make them look a lot bigger than they really are. At 4 1/2"W x 13"D x 41"H they are small towers but from what Danny says with really big sound. From my experience with these LGK drivers in my desktop speakers and Wedgies I can believe it. Since the Skinny 6's are -3dB at 70Hz you would need one of the servo subs to go with them.
Another option would be the bookshelves paired with one of Danny's 12" sealed servo subs. In my living room I have a pair of N3 towers (the ones in my avatar) paired with one 12" sealed servo sub. I cross the towers to the subs at 40Hz. With the X-LS Encores, X-CS Encores or the Skinny 6's you would cross over to the subs around 80Hz.
If you have never heard one of the GR-Research/Rythmik Direct Servo subs you might be inclined to think sub woofers cannot be musical nor could they blend well or keep up with main speakers. Nothing could be further from the truth with these.
Mike