Yes, for S2 and Note, sometime in the first quarter of 2012.

Actually, as far as I know, all the the SGS1 stock firmware do tend to lag.

On the contrary, when I first bought my sgs with eclair onboard, the phone was next to useless until ext2 lagfixes appeared.

Even now, since my wife is using my sgs, I always keep stock rom with rooted kernel and lagfix on the phone. This ensures that all the stock features work well but still sped up by the lagfix.