First I would suggest downloading LR and experimenting with the 30 day trial. See what you think. I use LR 90% of the time but still need both PS and LR, although my utility for LR vs PS is not in line with the pricing.
B&W: Not as many choices, but very good conversion UI. In PS there are 20 ways (200?) to do B&W conversions; in LR maybe 5.
Infrared: Sort of. You can increase the luminance of various colors to approach an infrared look, but I wouldn't call it very functional.
Stitching: Nope
Sharpening: Not as many choices, but almost as functional, if not better in some situations.
Noise reduction: Not as many choices. I've never directly compared the results.
Upressing: I don't know...
Selections: No, but it has a pretty nifty auto mask capability, and you can locally apply several adjustments.
Red eye: Yes.
Perspective control: Nope.
LR is quicker: Well, not exactly. This depends on what you are doing. I believe the overall workflow is much faster. However, you are always in a database when LR is open. In PS you can work with just one image file open, so processing-wise there are some things that PS can probably do faster, and vice versa.
Dave Chew