Second-rowers who will probably be here in 2012: Mannering, Mateo, Henry, Taylor, Ikahihifo, Palavi, StRapira, Sam Lousi. I wouldn't worry too much about our second-row depth.
To suggest we won't have depth next year is just not true. Analyse it:
Fullback: Locke, Fisiahii, Slaimankel (possibly). Fine.
Wing: Vatuvei, Tupou, Slaimankel (possibly). Depth not really here.
Centre: Nielsen, Hurrell, Ropati, Tuimavave, Penehe, Henry (if nedeed) Fine.
Halves: Johnson, Leuluai, Tuimamave, Godinet. Not completely flush but pretty standard situation
Props: Packer, Matulino, Lillyman, SaRapira, Sione Lousi, juniors. Fine.
Hooker: Friend, Leuluai (maybe), Mara, Godinet. Fine
Second-row: Flush, as above.
So if we're looking for a signing, I'd suggest wing is the place we should be targeting. Up in the air on Leuluai but he can make that position his own as well. Otherwise, that's depth to me.