I haven't tried Win7, but here are a few obvious performance enhancements for SSDs that all OSs should be doing:
1. Make sure the MBR and each partition reserves 64 sectors, not 63. Because SSDs are a completely new technology, they aren't build to the old-style Cylinder, Head, Sector format or the 512-bytes-per-sector format. SSDs have a "page" size of 32KB. Because of backwards compatibility, OSs format a drive so that the first 63 sectors (one entire track/head) are reserved. This was done because in CHS mode, there can be a maximum of 63 sectors per track (for some reason, sector numbering started with 1 instead of 0). Reserving 63 sectors would be bad for SSDs because that would mean the data would start on sector 64, which would be the last 512 bytes of the first 32KB page (in other words, more read/write cycles than otherwise needed).
2. More importantly, make sure the cluster/node size is 32KB (to match the smallest write the SSD can do). NTFS' default size if 4KB. Yes, using a size of 32KB will result is more wasted space, but it also means 32KB writes instead of 4KB writes, so it should improve performance due to fewer read/write cycles (by writing the full 32KB, you would write the entire page instead of writing only a portion of it which would require a read/write).
3. Make sure that the size of all non-file data (directory entries, file allocation / node tables, etc) is a multiple of 32KB to ensure that it doesn't cross a page boundary (which could result in additional read/write cycles).
----- Battery-backed RAMdrives
As for the idea of battery-backed RAMdrives, it's not really a feasible idea. It would be great from a performance standpoint, and it's definitely a good idea for short-term storage. But for long-term storage, it's too risky (too high of a risk of data loss due to loss of power), too little capacity per price point (though perhaps better than or comparable to SSDs), and too heavy (due to battery weight).
Let's use as an example the Kingston 2GB 1066MHz DDR2 memory module, part number KHX8500D2/2G. That module runs at 800MHz at 1.8V and uses 1.584W, giving us an amperage of 0.88A. It runs at 1066MHz at 2.2V (using approximately 1.936W). To get a 64GB RAMdrive, we would need 32 modules, giving us a total power draw of 50.688W (800MHz) or 61.952W (1066MHz).
A high-capacity Ni-Cad rechargeable AA battery yields 2000mAh at 1.2V, giving us approximately 2.64Wh. To power that 64GB RAMdrive at 800MHz for only one hour, you would need 20 batteries; to power it at 1066MHz for one hour, you would need 24 batteries.
A 12-cell Dell Li-Ion battery yields 96Wh at 14.8V, at a cost of $142, weighing 1.3 lbs. This battery could power that 64GB RAMdrive for only 1h53m (800MHz) or 1h32m (1066MHz).
As you can see, a high-capacity, battery-backed RAMdrive just isn't feasible. It would draw too much power and it would be too heavy. Compare this 64GB RAMdrive at 51W (over $1000) to a WD (model WD5000BEVT) 500GB 2.5" SATA-II hard drive at 2.5W ($100) or the Intel X25-E Extreme (model SSDSA2SH064G1C5) SLC SSD at 2.6W ($799).