Just played the MP beta for a bit, this is what I have to say about it.
Good:
* More tactical awareness required than CoD
* Less obnoxious children playing than CoD/BF3 (this is a closed beta though, subject to change)
* In-depth yet quasi-realistic weapon customization
* Both maps, while small, are still better than MW3 maps
Bad:
* Lag, expect TDU2-esque servers on release
* Pistols slightly underpowered compared to other Tom Clancy games (SC: Conviction and R6 Vegas 2 come to mind), however still better than BF3 or MW3
* Ubisoft will likely drop support of this game early, in tradition with other releases
* Always-on DRM (PC Only)
* No way of switching a weapon's fire mode without an attachment, makes some weapons difficult to use and lowers realism
* Not a full tactical shooter compared to previous GR games
My verdict: Don't buy.