A couple things:
You can turn your windows photoshop license into a mac one. Call them.
Aperture has a free demo now.
Don't overlook iPhoto. I used it for years, and found it to work well for managing smaller libraries. I'd make a library for each trip, and the 1-5 star system works great for selecting.
I tried many things to manage my master library. I wanted some things, like iptc, that iPhoto didn't do. But don't overlook simple stuff, like iPhoto and simple folders with good filenames and spotlight searches.
I like aperture better than other things I've tried, including iPhoto, for the fast raw support, the use of stacks for selecting from many similar images (I tend to shoot a lot of the same subject. Stacks are great, but there is a learning curve). I do very little editing other than cropping, so aperture's tools are fine for me.
I do still have to go over to photoshop for some things. There are some images that, for whatever reason (like a rare paper nautilus) that I need to do a lot of work on, with adjustment layers, interpolating for prints, fancy sharpening, and you just plain need photoshop.
That said, if I could only pick one, it would be aperture. I need it too badly to turn 100 pictures into the 4 good ones from a dive.
aperture's backups are great. So easy that I actually use it, and it saved me when a power problem on a liveaboard put my laptop in a coma.
I'd love to get rid of photoshop. Adobe seems to get worse and worse, at least on the mac. The interface just gets in my way more and more, I find it unusable for working on anything more than one photo at a time, all the add-ons they've plugged in just don't work for me. I have one machine on which photoshop will no longer update. I have another on which the help system won't run. When I re-installed, I ran out of licenses and had to call them. And even now, it has junk scattered over my hard drive (do I need this stock photo junk?) but I'm afraid to touch any of it because the program is so fragile. Dump some raw files on photoshop, and in ACR they show up in random order, it's impossible to make selects from a group on the same subject. Work in bridge and you're often looking at an old pixellated thumbnail. Without preview images, aperture could be slow, but at least you were always looking at the real image.
The point of that rant is, just as many people had trouble trusting their whole library to an aperture database, I have a problem trusting mine to adobe and lightroom.
That said, I'm really glad lightroom exists, it will make aperture better, it's already made it cheaper and probably created the free demo. THere are other things as well, like photo mechanic and extensis portfolio.
these library management tools have different features and different strengths. They do 3 things for me: help me select photos. Help me improve/edit photos. Help me manage my library. They all do different parts of that differently. We all do things different ways and have different needs. No one piece of software will solve all 3 problems for everyone. Nice to have choices.
Be aware that the more powerful the tool, the more of a learning curve there can be. If you do the free trials, give them a fair chance. Look at some of the online tutorials, too.