Yes, but on some routes this means frequency will decrease. MEM-CVG is currently 2x daily on CRJ2 but is going to 1x CRJ9 in May.
I will actually prefer this. There a lot of times where I've been presented with going through CVG as an option. I never pick it because I will not book a flight on CRJ200 unless I absolutely, positively must do so. Hell, I'll connect via ATL to CVG to avoid a nonstop on the RJ200.
Changing to a CRJ900 will make me actually consider utilizing CVG. (Although it's still tough to argue against just going to ATL and then pretty much anywhere, when MEM-ATL runs 10-11 times per day.)