The Japanese car maker has released additional details and also put a price tag on the 2011 Lexus IS F.
The 2011 Lexus IS F sports saloon powered by its 5.0-litre V8 that unleashes 417 bhp, is now Euro 5 compliant, while CO2 emissions and fuel consumption figures remain unchanged. The 2011 Lexus IS F equipped with the 8-speed Sport Direct Shift (SPDS) automatic transmissionis is also maintaining its nought to 62 mph acceleration time of 4.8 seconds, while top speed is limited to 168 mph.
Besides adding a limited slip differential on the 2011 Lexus IS F, some other tweaks performed by the Japanese company include a revised coilover suspension and shock absorbers and a slightly modified geometry for the rear suspension. All these enable the 2011 Lexus IS F to offer improved ride comfort as well as better handling and stability. 
The 2011 Lexus IS F price starts at 57,105 GBP. 
Lexus press release :
Change for change’s sake is rarely worthwhile, particularly when you
are dealing with such a well-defined concept as Lexus’s ultra-high
performance IS F sports saloon. So it is that the new 2011 IS F differs
from its predecessor in only a few well-thought-out details.
The principal change is that the mighty 417bhp 5.0-litre V8 engine
has been brought in line with Euro 5 emissions standards, a task
accomplished without impacting on its performance. The IS F, equipped
with an eight-speed Sport Direct Shift (SPDS) automatic transmission,
maintains its nought to 62mph acceleration time of 4.8 seconds and
168mph (electronically limited) top speed; CO2 emissions and fuel
consumption are also unaffected.
For 2010 the car’s handling and stability were enhanced with the
addition of a limited slip differential; in the latest raft of
engineering adjustments, the front and rear coil springs and shock
absorbers have been revised to improve ride comfort. The rear suspension
geometry has also been tweaked to gain greater stability under higher
loads when accelerating, braking and cornering. The result is all-round
advances in damping control, cornering stability and steering response.
The IS F’s high intensity discharge (HID) headlights are now paired
with new LED daytime running lights, configured to echo Lexus’s
signature arrowhead styling motif.
In the cabin the instrument binnacle has been redesigned, placing the
tachometer and gear shift indicator in the centre of the display. New
dark silver carbon fibre-style trim details have also been added.
The 2011 IS F is on sale now, price £57,105 on the road.

Source: Lexus