To actually answer the question.....
The changes being made are still aimed at the grand scheme of cost cutting. This has mean reduced develoment costs, less time testing, parts lasting longer, penalties for changing parts. Most of which has come in one form or another this year. We will slowly see cars become more standardised and the gap between the front runners and useless cars tighten as development budgets are brought in line. One of the rules such as no TC was brough forward early a year, these rules were proposed a few years ago.
Some of the major changes for 2009 are... ( i dont know if they are all still relevant)
A change in the size of the cars: The maximum width will increase from 1800mm to 2000mm, with the minimum width being 1980mm. The wheels will also increase in size, from 355mm to 365mm at the front, and from 380mm to 460mm.
- A change to the weight: To accommodate the energy recovery systems, the minimum weight of the cars is increasing from 600kg to 605kg.
- Standard ECUs will be introduced, and Traction Control will therefore be banned as allready has been in 2008.
- Lights inside the cockpit to warn drivers of flags being shown on parts of the circuits. One issue that has been going on for a while is the difficulty drivers have of seeing flags being waved on the side of the circuit when they are driving at high speed. The lights would corrospond with the flag being waved, and go out when the driver has passed the affected area.
- Pit-to-car radios must no longer be scrambled. This is probably to aid the television companies as the recent introduction of radio messages during live broadcasts has proved popular.
- Kinetic Energy Recovery Systems, essentially a push-to-pass system powered by stored braking energy, will become mandatory for 2009
Here is an interview with Nick Heidfeld who tested a 2009 spec BMW on slicks.
http://f1.gpupdate.net/en/news/2007/12/05/heidfeld-f1-wil-be-extremely-dangerous-in-2009/And in depth article into the changes.
http://www.itv-f1.com/Feature.aspx?Type=Mark_Hughes&id=42353and if your really interested....the full FIA Documentation
http://www.fia.com/resources/documents/1151088479__2009_F1_TECHNICAL_REGULATIONS.pdf