Lenovo's venerable ThinkPad line has undergone an update following 18 months of planning. The first system to showcase the redesign is the just-announced ThinkPad T431s Ultrabook. It's still very much a ThinkPad at heart but it's been put on a diet and given some subtle, understated changes.

Overall, the system looks a bit more refined than previous ThinkPad shells. Gone are the various hooks, latches and bumpers as well as the physical mouse click buttons. Lenovo says it took two years of working with Synaptics to perfect the trackpad drivers. It is also much wider than before while the screen bezel is the thinnest ever on a T-series ThinkPad.

The 14-inch T431s Ultrabook ships with an impressive-sounding 1,600 x 900 matte display carrying 250 nits of brightness. Entry level systems will carry an Intel Core i5-3337U processor clocked at 2.7GHz, Intel HD Graphics, 4GB of RAM, a 320GB 5,400 RPM hard drive and your choice of Windows 7 or Windows 8. If you need a bit more power and speed, you can spring for a Core i7 CPU, up to 12GB of RAM and a solid state drive.

Common features include an Ethernet jack, VGA connector, 3.5mm headphone / microphone combo jack, two USB 3.0 ports, a 4-in-1 card reader, a 47WHr three-cell battery, Bluetooth 4.0, Wi-Fi and WWAN connections. The system measures 13.03 x 8.89 x 0.8 inches and weighs just 3.6 pounds. An optional backlit keyboard is available should you choose.

The Lenovo T431s Ultrabook will be available in April starting at $949.