The 2008
points charts are available already, just not on the members' website yet. If you call MS and tell them the dates, they will give you the points. I called them 3 weeks ago and found that the points actually went down for the lowest season for both Disneyland Hotel and the Grand. There is no booking window for the DLR hotels. As long as the points chart is available to MS, they can put in a reservation request for you.
I know many people believe using points at DLR hotels is not a good use of points. However, I think that using points for a peak period reservation at the Grand is totally worth it. I used 106 points for a 3-night stay there during August when the hotel was totally sold out. AP rate during peak times is just a meager 10% off rack rate, unlike off-peak discounts of up to 50%. Paying cash for those 3 nights at the AP rate would have cost me $1080 before tax and resort fee which would add another hundred or two to the bill.
I agree that renting points though would not be worth it assuming you have to pay $10+ per point. I just want to point out that for members, it may be worth doing if you go at peak times when the hotels at DLR do not offer any attractive discounts.