Long time Migration of macs (over 80 hours)
Yeah, I have had similar experiences with WiFi transfers involving large amounts of data. The good news is that if you are extremely patient it will probably work out OK. The other good news is that if you have not messed with the factory partitioning scheme it doesn't matter that you can't install from CD/DVD. 

If you do choose to restart the whole process - by resetting your new machine to original configuration with the Lion Recovery Partition - then a Migration using Target Disk Mode and the right FireWire 800 cable will probably take only an hour or so to complete.