In a word...
Ok, now that I've got that out of my system...
As I said in the blurb there isn't much change to the prospects manning the box behind the dish from last year, but there also hasn't been a whole lot of growth either developmentally or in the form of trades or draft picks from 2014. In reality, most teams don't have a whole lot of talent in the minor leagues behind the plate, but the Cardinals are really abusing the mediocrity privilege with this roster of cast-offs and not-quite-good-enoughs and not-sure-he-can-play-the-position-defensively's.
Mike Ohlman: A guy that Orioles basically gave up on as a catcher and didn't figure had the bat to play 1B -- and this is in an organization that isn't exactly overflowing with backstops either -- their big league stud still isn't all the way back from Tommy John surgery. The Cardinals acquired him for cash considerations near the end of March and Aaron Finkel wrote up a post on Ohlman at that time.
Ohlman is 6'5", not the ideal build for a catcher, and doesn't have the power bat typically found in any sort of corner infield type (career .127 ISO in the minors) so he's really just a man without a position.
Brian O'Keefe - A 7th round selection out of St. Joseph's last June, O'Keefe didn't show a lot of promise with State College last season hitting just .239/.366/.348 in 187 PA's for the Spikes. He was a bit young for a draft eligible junior though, turning 21 just last July, so there's a bit time for some development. Getting some better luck (264 BABIP) would go a long way towards establishing some confidence at the plate to go along with what most scouts seem to think is solidly above average defense behind the plate.
Carson Kelly - If you haven't read his Top 25 profile, I suggest you do so as I'm not going to repeat it here. Once you get done there, read his interview with Joe Schwarz from February of 2014 as well.
Cody Stanley - The definition of a Jekyll and Hyde prospect, Stanley's tools have always looked better than his results up until last season when he finally seemed to be coming out of his shell, hitting .283/.340/.429 with 12 homers in 433 PA's for Springfield. A full quarter of his games came at DH (27) rather than catcher (76) and there's still some questions about his ability defensively, although there are some reports of improvement to "average-ish". My belief is that scouts are valuing Stanley's ability as a receiver/framer more than they did in the past, as his arm is still just average and he doesn't have the quick feet you normally find in a good defensive backstop either.
The question is whether you believe in the bat. If you do, then Stanley's left handedness and good-enough defense make him a cheap and useful backup catcher when Tony Cruz gets more expensive in his second year of arbitration next year. I'm not in that crowd -- I'm in the camp that is fairly certain Stanley's 2014 was a Hammons Field mirage, as we've seen so often over the years from left handed hitters. Thus far, Stanley's .256 wOBA at AAA in 2015 doesn't inspire a whole lot of confidence, although it is still early (just 80 PA's so far) and it is his first time through the PCL as well.
Steve Bean - I don't think he can catch, Joe doesn't think he can catch...yet our opinions are at odds with a lot of scouts apparently, who seem to think that he's an above average catcher. Bean does have a nice arm, for sure, but he's not a good receiver, makes poor decisions at times, although he does get some credit around the farm for calling a pretty solid game behind the plate. He's just a year older than Kelly, and still hasn't ever hit much at all, but he was a top 100 pick once upon a time, so there's still some chance to live up to that promise.
As the Cardinals head into the draft, catcher is certainly a position of need within the organization. Carson Kelly is anything but a sure thing, Yadier Molina isn't getting any younger, and just about any catcher who is going to be groomed at all by the future Cardinals Hall of Famer is likely going to have to enter the organization this year.
Given the state of catching prospects, however, every other team is also going to be looking for catching help in a draft that seems really short of quality players at the position. Not to mention that the Cardinals spent high draft picks on Steve Bean (still around, struggling) and Robert Stock (stunk, moved the mound, stunk worse, and is now out of the organization) and neither has made it out of A ball over the last half decade.
Catcher is certainly a need, but I can't see much reason to think the Cardinals will be able to fill it short of a mid-to-late round miracle.